Created by William Kapke
kangax's compat-table applied only to Node.js
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Node.js ES2015 Support

24.0.0
(these versions have identical results)
nightly v8 12.9.202.28-node.11
Nightly!99% complete99% complete 		23.3.0
(these versions have identical results)
23.3.0 v8 12.9.202.28-node.11
99% complete99% complete 		23.2.0
(these versions have identical results)
23.2.0 v8 12.9.202.28-node.11
23.1.0 v8 12.9.202.28-node.11
23.0.0 v8 12.9.202.26-node.10
99% complete99% complete 		22.11.0
(these versions have identical results)
22.11.0 v8 12.4.254.21-node.21
22.10.0 v8 12.4.254.21-node.21
22.9.0 v8 12.4.254.21-node.19
22.8.0 v8 12.4.254.21-node.19
22.7.0 v8 12.4.254.21-node.18
22.6.0 v8 12.4.254.21-node.18
22.5.1 v8 12.4.254.21-node.16
22.5.0 v8 12.4.254.21-node.16
22.4.1 v8 12.4.254.21-node.15
22.4.0 v8 12.4.254.21-node.15
22.3.0 v8 12.4.254.20-node.13
22.2.0 v8 12.4.254.14-node.12
22.1.0 v8 12.4.254.14-node.11
22.0.0 v8 12.4.254.14-node.10
99% complete99% complete 		21.7.3
(these versions have identical results)
21.7.3 v8 11.8.172.17-node.20
21.7.2 v8 11.8.172.17-node.20
21.7.1 v8 11.8.172.17-node.20
21.7.0 v8 11.8.172.17-node.20
21.6.2 v8 11.8.172.17-node.19
21.6.1 v8 11.8.172.17-node.19
21.6.0 v8 11.8.172.17-node.19
21.5.0 v8 11.8.172.17-node.18
21.4.0 v8 11.8.172.17-node.17
21.3.0 v8 11.8.172.17-node.17
99% complete99% complete 		21.2.0
(these versions have identical results)
21.2.0 v8 11.8.172.17-node.15
21.1.0 v8 11.8.172.15-node.14
21.0.0 v8 11.8.172.13-node.12
99% complete99% complete 		20.18.1
(these versions have identical results)
20.18.1 v8 11.3.244.8-node.23
20.18.0 v8 11.3.244.8-node.23
20.17.0 v8 11.3.244.8-node.23
20.16.0 v8 11.3.244.8-node.23
20.15.1 v8 11.3.244.8-node.23
20.15.0 v8 11.3.244.8-node.23
20.14.0 v8 11.3.244.8-node.23
20.13.1 v8 11.3.244.8-node.20
20.13.0 v8 11.3.244.8-node.20
20.12.2 v8 11.3.244.8-node.19
20.12.1 v8 11.3.244.8-node.19
20.12.0 v8 11.3.244.8-node.19
99% complete99% complete 		20.11.1
(these versions have identical results)
20.11.1 v8 11.3.244.8-node.17
20.11.0 v8 11.3.244.8-node.17
20.10.0 v8 11.3.244.8-node.25
20.9.0 v8 11.3.244.8-node.16
20.8.1 v8 11.3.244.8-node.16
20.8.0 v8 11.3.244.8-node.16
20.7.0 v8 11.3.244.8-node.15
20.6.1 v8 11.3.244.8-node.14
20.6.0 v8 11.3.244.8-node.14
20.5.1 v8 11.3.244.8-node.10
20.5.0 v8 11.3.244.8-node.10
20.4.0 v8 11.3.244.8-node.10
20.3.1 v8 11.3.244.8-node.9
20.3.0 v8 11.3.244.8-node.9
20.2.0 v8 11.3.244.8-node.9
20.1.0 v8 11.3.244.8-node.6
20.0.0 v8 11.3.244.4-node.3
99% complete99% complete 		19.9.0
(these versions have identical results)
19.9.0 v8 10.8.168.25-node.16
19.8.1 v8 10.8.168.25-node.12
19.8.0 v8 10.8.168.25-node.12
19.7.0 v8 10.8.168.25-node.11
19.6.1 v8 10.8.168.25-node.11
19.6.0 v8 10.8.168.25-node.11
19.5.0 v8 10.8.168.25-node.11
19.4.0 v8 10.8.168.25-node.11
19.3.0 v8 10.8.168.21-node.8
19.2.0 v8 10.8.168.20-node.8
99% complete99% complete 		19.1.0
(these versions have identical results)
19.1.0 v8 10.7.193.20-node.19
99% complete99% complete 		19.0.1
(these versions have identical results)
19.0.1 v8 10.7.193.13-node.16
19.0.0 v8 10.7.193.13-node.16
99% complete99% complete 		18.20.5
(these versions have identical results)
18.20.5 v8 10.2.154.26-node.37
18.20.4 v8 10.2.154.26-node.37
18.20.3 v8 10.2.154.26-node.37
18.20.2 v8 10.2.154.26-node.36
18.20.1 v8 10.2.154.26-node.36
18.20.0 v8 10.2.154.26-node.36
99% complete99% complete 		18.19.1
(these versions have identical results)
18.19.1 v8 10.2.154.26-node.28
18.19.0 v8 10.2.154.26-node.28
18.18.2 v8 10.2.154.26-node.26
18.18.1 v8 10.2.154.26-node.26
18.18.0 v8 10.2.154.26-node.26
18.17.1 v8 10.2.154.26-node.26
18.17.0 v8 10.2.154.26-node.26
18.16.1 v8 10.2.154.26-node.26
18.16.0 v8 10.2.154.26-node.26
18.15.0 v8 10.2.154.26-node.25
18.14.2 v8 10.2.154.26-node.22
18.14.1 v8 10.2.154.23-node.22
18.14.0 v8 10.2.154.23-node.22
18.13.0 v8 10.2.154.23-node.21
99% complete99% complete 		18.12.1
(these versions have identical results)
18.12.1 v8 10.2.154.15-node.12
18.12.0 v8 10.2.154.15-node.12
18.11.0 v8 10.2.154.15-node.12
18.10.0 v8 10.2.154.15-node.12
18.9.1 v8 10.2.154.15-node.12
18.9.0 v8 10.2.154.15-node.12
18.8.0 v8 10.2.154.13-node.11
18.7.0 v8 10.2.154.13-node.9
18.6.0 v8 10.2.154.13-node.8
18.5.0 v8 10.2.154.4-node.8
18.4.0 v8 10.2.154.4-node.8
18.3.0 v8 10.2.154.4-node.8
18.2.0 v8 10.1.124.8-node.13
18.1.0 v8 10.1.124.8-node.13
18.0.0 v8 10.1.124.8-node.13
99% complete99% complete 		17.9.1
(these versions have identical results)
17.9.1 v8 9.6.180.15-node.16
17.9.0 v8 9.6.180.15-node.16
17.8.0 v8 9.6.180.15-node.16
17.7.2 v8 9.6.180.15-node.15
17.7.1 v8 9.6.180.15-node.15
17.7.0 v8 9.6.180.15-node.15
17.6.0 v8 9.6.180.15-node.13
17.5.0 v8 9.6.180.15-node.13
17.4.0 v8 9.6.180.15-node.13
17.3.1 v8 9.6.180.15-node.12
17.3.0 v8 9.6.180.15-node.12
17.2.0 v8 9.6.180.14-node.12
99% complete99% complete 		17.1.0
(these versions have identical results)
17.1.0 v8 9.5.172.25-node.13
17.0.1 v8 9.5.172.21-node.12
17.0.0 v8 9.5.172.21-node.12
99% complete99% complete 		16.20.2
(these versions have identical results)
16.20.2 v8 9.4.146.26-node.26
16.20.1 v8 9.4.146.26-node.26
16.20.0 v8 9.4.146.26-node.26
16.19.1 v8 9.4.146.26-node.24
16.19.0 v8 9.4.146.26-node.24
16.18.1 v8 9.4.146.26-node.22
16.18.0 v8 9.4.146.26-node.22
16.17.1 v8 9.4.146.26-node.22
16.17.0 v8 9.4.146.26-node.22
16.16.0 v8 9.4.146.24-node.21
16.15.1 v8 9.4.146.24-node.21
16.15.0 v8 9.4.146.24-node.20
16.14.2 v8 9.4.146.24-node.20
16.14.1 v8 9.4.146.24-node.20
16.14.0 v8 9.4.146.24-node.20
99% complete99% complete 		16.13.2
(these versions have identical results)
16.13.2 v8 9.4.146.24-node.14
16.13.1 v8 9.4.146.24-node.14
16.13.0 v8 9.4.146.19-node.13
16.12.0 v8 9.4.146.19-node.13
16.11.1 v8 9.4.146.19-node.13
16.11.0 v8 9.4.146.19-node.13
99% complete99% complete 		16.10.0
(these versions have identical results)
16.10.0 v8 9.3.345.19-node.14
16.9.1 v8 9.3.345.16-node.12
16.9.0 v8 9.3.345.16-node.11
99% complete99% complete 		16.8.0
(these versions have identical results)
16.8.0 v8 9.2.230.21-node.20
16.7.0 v8 9.2.230.21-node.19
16.6.2 v8 9.2.230.21-node.19
16.6.1 v8 9.2.230.21-node.19
16.6.0 v8 9.2.230.21-node.18
99% complete99% complete 		16.5.0
(these versions have identical results)
16.5.0 v8 9.1.269.38-node.20
16.4.2 v8 9.1.269.36-node.14
16.4.1 v8 9.1.269.36-node.14
16.4.0 v8 9.1.269.36-node.14
99% complete99% complete 		16.3.0
(these versions have identical results)
16.3.0 v8 9.0.257.25-node.16
16.2.0 v8 9.0.257.25-node.16
16.1.0 v8 9.0.257.24-node.11
99% complete99% complete 		16.0.0
(these versions have identical results)
16.0.0 v8 9.0.257.17-node.10
99% complete99% complete 		15.14.0
(these versions have identical results)
15.14.0 v8 8.6.395.17-node.28
15.13.0 v8 8.6.395.17-node.28
15.12.0 v8 8.6.395.17-node.27
15.11.0 v8 8.6.395.17-node.27
15.10.0 v8 8.6.395.17-node.25
15.9.0 v8 8.6.395.17-node.25
15.8.0 v8 8.6.395.17-node.23
15.7.0 v8 8.6.395.17-node.23
15.6.0 v8 8.6.395.17-node.23
15.5.1 v8 8.6.395.17-node.23
15.5.0 v8 8.6.395.17-node.23
15.4.0 v8 8.6.395.17-node.22
15.3.0 v8 8.6.395.17-node.22
15.2.1 v8 8.6.395.17-node.17
15.2.0 v8 8.6.395.17-node.17
15.1.0 v8 8.6.395.17-node.16
15.0.1 v8 8.6.395.17-node.15
15.0.0 v8 8.6.395.16-node.15
99% complete99% complete 		14.21.3
(these versions have identical results)
14.21.3 v8 8.4.371.23-node.88
14.21.2 v8 8.4.371.23-node.88
14.21.1 v8 8.4.371.23-node.87
14.21.0 v8 8.4.371.23-node.87
14.20.1 v8 8.4.371.23-node.87
14.20.0 v8 8.4.371.23-node.87
14.19.3 v8 8.4.371.23-node.87
14.19.2 v8 8.4.371.23-node.87
14.19.1 v8 8.4.371.23-node.85
14.19.0 v8 8.4.371.23-node.85
99% complete99% complete 		14.18.3
(these versions have identical results)
14.18.3 v8 8.4.371.23-node.85
14.18.2 v8 8.4.371.23-node.85
14.18.1 v8 8.4.371.23-node.84
14.18.0 v8 8.4.371.23-node.84
14.17.6 v8 8.4.371.23-node.76
14.17.5 v8 8.4.371.23-node.76
14.17.4 v8 8.4.371.23-node.76
14.17.3 v8 8.4.371.23-node.67
14.17.2 v8 8.4.371.23-node.67
14.17.1 v8 8.4.371.23-node.67
14.17.0 v8 8.4.371.23-node.63
14.16.1 v8 8.4.371.19-node.18
14.16.0 v8 8.4.371.19-node.18
14.15.5 v8 8.4.371.19-node.18
14.15.4 v8 8.4.371.19-node.17
14.15.3 v8 8.4.371.19-node.17
14.15.2 v8 8.4.371.19-node.17
14.15.1 v8 8.4.371.19-node.17
14.15.0 v8 8.4.371.19-node.17
14.14.0 v8 8.4.371.19-node.17
14.13.1 v8 8.4.371.19-node.16
14.13.0 v8 8.4.371.19-node.16
14.12.0 v8 8.4.371.19-node.16
14.11.0 v8 8.4.371.19-node.16
14.10.1 v8 8.4.371.19-node.16
14.10.0 v8 8.4.371.19-node.16
14.9.0 v8 8.4.371.19-node.13
14.8.0 v8 8.4.371.19-node.12
14.7.0 v8 8.4.371.19-node.12
14.6.0 v8 8.4.371.19-node.12
99% complete99% complete 		14.5.0
(these versions have identical results)
14.5.0 v8 8.3.110.9-node.23
14.4.0 v8 8.1.307.31-node.33
14.3.0 v8 8.1.307.31-node.33
14.2.0 v8 8.1.307.31-node.33
14.1.0 v8 8.1.307.31-node.32
14.0.0 v8 8.1.307.30-node.30
99% complete99% complete 		13.14.0
(these versions have identical results)
13.14.0 v8 7.9.317.25-node.32
13.13.0 v8 7.9.317.25-node.30
13.12.0 v8 7.9.317.25-node.30
99% complete99% complete 		13.11.0
(these versions have identical results)
13.11.0 v8 7.9.317.25-node.29
13.10.1 v8 7.9.317.25-node.29
13.10.0 v8 7.9.317.25-node.29
13.9.0 v8 7.9.317.25-node.28
13.8.0 v8 7.9.317.25-node.28
13.7.0 v8 7.9.317.25-node.28
13.6.0 v8 7.9.317.25-node.26
13.5.0 v8 7.9.317.25-node.23
13.4.0 v8 7.9.317.25-node.23
13.3.0 v8 7.9.317.25-node.23
13.2.0 v8 7.9.317.23-node.20
99% complete99% complete 		13.1.0
(these versions have identical results)
13.1.0 v8 7.8.279.17-node.19
13.0.1 v8 7.8.279.17-node.14
13.0.0 v8 7.8.279.17-node.14
99% complete99% complete 		12.22.12
(these versions have identical results)
12.22.12 v8 7.8.279.23-node.57
12.22.11 v8 7.8.279.23-node.56
12.22.10 v8 7.8.279.23-node.56
12.22.9 v8 7.8.279.23-node.56
12.22.8 v8 7.8.279.23-node.56
12.22.7 v8 7.8.279.23-node.56
12.22.6 v8 7.8.279.23-node.56
12.22.5 v8 7.8.279.23-node.56
12.22.4 v8 7.8.279.23-node.56
12.22.3 v8 7.8.279.23-node.46
12.22.2 v8 7.8.279.23-node.46
12.22.1 v8 7.8.279.23-node.46
12.22.0 v8 7.8.279.23-node.46
12.21.0 v8 7.8.279.23-node.45
12.20.2 v8 7.8.279.23-node.45
12.20.1 v8 7.8.279.23-node.45
12.20.0 v8 7.8.279.23-node.45
12.19.1 v8 7.8.279.23-node.44
12.19.0 v8 7.8.279.23-node.44
12.18.4 v8 7.8.279.23-node.39
12.18.3 v8 7.8.279.23-node.39
12.18.2 v8 7.8.279.23-node.39
12.18.1 v8 7.8.279.23-node.38
12.18.0 v8 7.8.279.23-node.37
12.17.0 v8 7.8.279.23-node.37
99% complete99% complete 		12.16.3
(these versions have identical results)
12.16.3 v8 7.8.279.23-node.35
12.16.2 v8 7.8.279.23-node.34
12.16.1 v8 7.8.279.23-node.31
12.16.0 v8 7.8.279.23-node.31
12.15.0 v8 7.7.299.13-node.16
12.14.1 v8 7.7.299.13-node.16
12.14.0 v8 7.7.299.13-node.16
12.13.1 v8 7.7.299.13-node.16
12.13.0 v8 7.7.299.13-node.12
12.12.0 v8 7.7.299.13-node.12
12.11.1 v8 7.7.299.11-node.12
12.11.0 v8 7.7.299.11-node.12
99% complete99% complete 		12.10.0
(these versions have identical results)
12.10.0 v8 7.6.303.29-node.16
12.9.1 v8 7.6.303.29-node.15
12.9.0 v8 7.6.303.29-node.15
99% complete99% complete 		12.8.1
(these versions have identical results)
12.8.1 v8 7.5.288.22-node.16
12.8.0 v8 7.5.288.22-node.16
12.7.0 v8 7.5.288.22-node.16
12.6.0 v8 7.5.288.22-node.14
12.5.0 v8 7.5.288.22-node.14
99% complete99% complete 		12.4.0
(these versions have identical results)
12.4.0 v8 7.4.288.27-node.18
12.3.1 v8 7.4.288.27-node.18
12.3.0 v8 7.4.288.27-node.17
12.2.0 v8 7.4.288.21-node.17
12.1.0 v8 7.4.288.21-node.16
99% complete99% complete 		12.0.0
(these versions have identical results)
12.0.0 v8 7.4.288.21-node.16
99% complete99% complete 		11.15.0
(these versions have identical results)
11.15.0 v8 7.0.276.38-node.19
11.14.0 v8 7.0.276.38-node.18
11.13.0 v8 7.0.276.38-node.18
11.12.0 v8 7.0.276.38-node.18
11.11.0 v8 7.0.276.38-node.18
11.10.1 v8 7.0.276.38-node.17
11.10.0 v8 7.0.276.38-node.17
11.9.0 v8 7.0.276.38-node.16
11.8.0 v8 7.0.276.38-node.16
11.7.0 v8 7.0.276.38-node.16
11.6.0 v8 7.0.276.38-node.13
11.5.0 v8 7.0.276.38-node.13
11.4.0 v8 7.0.276.38-node.13
11.3.0 v8 7.0.276.38-node.11
11.2.0 v8 7.0.276.38-node.11
11.1.0 v8 7.0.276.32-node.7
11.0.0 v8 7.0.276.28-node.5
99% complete99% complete 		10.24.1
(these versions have identical results)
10.24.1 v8 6.8.275.32-node.59
10.24.0 v8 6.8.275.32-node.59
10.23.3 v8 6.8.275.32-node.59
10.23.2 v8 6.8.275.32-node.59
10.23.1 v8 6.8.275.32-node.59
10.23.0 v8 6.8.275.32-node.59
10.22.1 v8 6.8.275.32-node.58
10.22.0 v8 6.8.275.32-node.58
10.21.0 v8 6.8.275.32-node.56
10.20.1 v8 6.8.275.32-node.56
10.20.0 v8 6.8.275.32-node.56
10.19.0 v8 6.8.275.32-node.55
10.18.1 v8 6.8.275.32-node.55
10.18.0 v8 6.8.275.32-node.54
10.17.0 v8 6.8.275.32-node.54
10.16.3 v8 6.8.275.32-node.54
10.16.2 v8 6.8.275.32-node.54
10.16.1 v8 6.8.275.32-node.54
10.16.0 v8 6.8.275.32-node.52
99% complete99% complete 		10.15.3
(these versions have identical results)
10.15.3 v8 6.8.275.32-node.51
10.15.2 v8 6.8.275.32-node.12
10.15.1 v8 6.8.275.32-node.12
10.15.0 v8 6.8.275.32-node.45
10.14.2 v8 6.8.275.32-node.45
10.14.1 v8 6.8.275.32-node.36
10.14.0 v8 6.8.275.32-node.36
10.13.0 v8 6.8.275.32-node.36
10.12.0 v8 6.8.275.32-node.35
10.11.0 v8 6.8.275.32-node.28
10.10.0 v8 6.8.275.30-node.24
10.9.0 v8 6.8.275.24-node.14
99% complete99% complete 		10.8.0
(these versions have identical results)
10.8.0 v8 6.7.288.49-node.19
10.7.0 v8 6.7.288.49-node.15
10.6.0 v8 6.7.288.46-node.13
99% complete99% complete 		10.5.0
(these versions have identical results)
10.5.0 v8 6.7.288.46-node.8
10.4.1 v8 6.7.288.45-node.7
10.4.0 v8 6.7.288.43-node.7
99% complete99% complete 		10.3.0
(these versions have identical results)
10.3.0 v8 6.6.346.32-node.9
10.2.1 v8 6.6.346.32-node.8
10.2.0 v8 6.6.346.32-node.8
10.1.0 v8 6.6.346.27-node.6
10.0.0 v8 6.6.346.24-node.5
99% complete99% complete 		9.11.2
(these versions have identical results)
9.11.2 v8 6.2.414.46-node.23
9.11.1 v8 6.2.414.46-node.23
9.11.0 v8 6.2.414.46-node.23
9.10.1 v8 6.2.414.46-node.23
9.10.0 v8 6.2.414.46-node.23
9.9.0 v8 6.2.414.46-node.22
9.8.0 v8 6.2.414.46-node.21
9.7.1 v8 6.2.414.46-node.20
9.7.0 v8 6.2.414.46-node.20
9.6.1 v8 6.2.414.46-node.20
9.6.0 v8 6.2.414.46-node.20
9.5.0 v8 6.2.414.46-node.18
9.4.0 v8 6.2.414.46-node.17
9.3.0 v8 6.2.414.46-node.15
9.2.1 v8 6.2.414.44-node.11
9.2.0 v8 6.2.414.44-node.11
9.1.0 v8 6.2.414.32-node.8
9.0.0 v8 6.2.414.32-node.8
8.17.0 v8 6.2.414.78
8.16.2 v8 6.2.414.78
8.16.1 v8 6.2.414.77
8.16.0 v8 6.2.414.77
8.15.1 v8 6.2.414.75
8.15.0 v8 6.2.414.75
8.14.1 v8 6.2.414.75
8.14.0 v8 6.2.414.72
8.13.0 v8 6.2.414.72
8.12.0 v8 6.2.414.66
8.11.4 v8 6.2.414.54
8.11.3 v8 6.2.414.54
8.11.2 v8 6.2.414.54
8.11.1 v8 6.2.414.50
8.11.0 v8 6.2.414.50
8.10.0 v8 6.2.414.50
99% complete99% complete 		8.9.4
(these versions have identical results)
8.9.4 v8 6.1.534.50
8.9.3 v8 6.1.534.48
8.9.2 v8 6.1.534.48
8.9.1 v8 6.1.534.47
8.9.0 v8 6.1.534.46
8.8.1 v8 6.1.534.42
8.8.0 v8 6.1.534.42
8.7.0 v8 6.1.534.42
99% complete99% complete 		8.6.0
(these versions have identical results)
8.6.0 v8 6.0.287.53
8.5.0 v8 6.0.287.53
8.4.0 v8 6.0.286.52
8.3.0 v8 6.0.286.52
99% complete99% complete 		8.2.1
(these versions have identical results)
8.2.1 v8 5.8.283.41
8.2.0 v8 5.8.283.41
8.1.4 v8 5.8.283.41
8.1.3 v8 5.8.283.41
8.1.2 v8 5.8.283.41
8.1.1 v8 5.8.283.41
8.1.0 v8 5.8.283.41
8.0.0 v8 5.8.283.41
99% complete99% complete 		7.10.1
(these versions have identical results)
7.10.1 v8 5.5.372.43
7.10.0 v8 5.5.372.43
7.9.0 v8 5.5.372.43
7.8.0 v8 5.5.372.43
7.7.4 v8 5.5.372.42
7.7.3 v8 5.5.372.41
7.7.2 v8 5.5.372.41
7.7.1 v8 5.5.372.41
7.7.0 v8 5.5.372.41
7.6.0 v8 5.5.372.40
99% complete98% complete 		7.5.0
(these versions have identical results)
7.5.0 v8 5.4.500.48
7.4.0 v8 5.4.500.45
7.3.0 v8 5.4.500.45
7.2.1 v8 5.4.500.44
7.2.0 v8 5.4.500.43
7.1.0 v8 5.4.500.36
7.0.0 v8 5.4.500.36
99% complete98% complete 		6.17.1
(these versions have identical results)
6.17.1 v8 5.1.281.111
6.17.0 v8 5.1.281.111
6.16.0 v8 5.1.281.111
6.15.1 v8 5.1.281.111
6.15.0 v8 5.1.281.111
6.14.4 v8 5.1.281.111
6.14.3 v8 5.1.281.111
6.14.2 v8 5.1.281.111
6.14.1 v8 5.1.281.111
6.14.0 v8 5.1.281.111
6.13.1 v8 5.1.281.111
6.13.0 v8 5.1.281.111
6.12.3 v8 5.1.281.111
6.12.2 v8 5.1.281.109
6.12.1 v8 5.1.281.109
6.12.0 v8 5.1.281.108
6.11.5 v8 5.1.281.108
6.11.4 v8 5.1.281.108
6.11.3 v8 5.1.281.107
6.11.2 v8 5.1.281.103
6.11.1 v8 5.1.281.103
6.11.0 v8 5.1.281.102
6.10.3 v8 5.1.281.101
6.10.2 v8 5.1.281.98
6.10.1 v8 5.1.281.95
6.10.0 v8 5.1.281.93
6.9.5 v8 5.1.281.89
6.9.4 v8 5.1.281.89
6.9.3 v8 5.1.281.89
6.9.2 v8 5.1.281.88
6.9.1 v8 5.1.281.84
6.9.0 v8 5.1.281.84
6.8.1 v8 5.1.281.84
6.8.0 v8 5.1.281.84
6.7.0 v8 5.1.281.83
6.6.0 v8 5.1.281.83
6.5.0 v8 5.1.281.81
99% complete98% complete 		6.4.0
(these versions have identical results)
6.4.0 v8 5.0.71.60
6.3.1 v8 5.0.71.57
6.3.0 v8 5.0.71.52
6.2.2 v8 5.0.71.52
6.2.1 v8 5.0.71.52
6.2.0 v8 5.0.71.47
6.1.0 v8 5.0.71.35
6.0.0 v8 5.0.71.35
95% complete91% complete 		5.12.0
(these versions have identical results)
5.12.0 v8 4.6.85.32
5.11.1 v8 4.6.85.31
5.11.0 v8 4.6.85.31
5.10.1 v8 4.6.85.31
5.10.0 v8 4.6.85.31
5.9.1 v8 4.6.85.31
5.9.0 v8 4.6.85.31
5.8.0 v8 4.6.85.31
5.7.1 v8 4.6.85.31
5.7.0 v8 4.6.85.31
5.6.0 v8 4.6.85.31
5.5.0 v8 4.6.85.31
5.4.1 v8 4.6.85.31
5.4.0 v8 4.6.85.31
5.3.0 v8 4.6.85.31
5.2.0 v8 4.6.85.31
5.1.1 v8 4.6.85.31
5.1.0 v8 4.6.85.31
5.0.0 v8 4.6.85.28
57% complete46% complete 		4.9.1
(these versions have identical results)
4.9.1 v8 4.5.103.53
4.9.0 v8 4.5.103.53
4.8.7 v8 4.5.103.53
4.8.6 v8 4.5.103.53
4.8.5 v8 4.5.103.47
4.8.4 v8 4.5.103.47
4.8.3 v8 4.5.103.47
4.8.2 v8 4.5.103.46
4.8.1 v8 4.5.103.46
4.8.0 v8 4.5.103.45
4.7.3 v8 4.5.103.43
4.7.2 v8 4.5.103.43
4.7.1 v8 4.5.103.43
4.7.0 v8 4.5.103.43
4.6.2 v8 4.5.103.42
4.6.1 v8 4.5.103.37
4.6.0 v8 4.5.103.37
4.5.0 v8 4.5.103.37
4.4.7 v8 4.5.103.36
4.4.6 v8 4.5.103.36
4.4.5 v8 4.5.103.35
4.4.4 v8 4.5.103.35
4.4.3 v8 4.5.103.35
4.4.2 v8 4.5.103.35
4.4.1 v8 4.5.103.35
4.4.0 v8 4.5.103.35
4.3.2 v8 4.5.103.35
4.3.1 v8 4.5.103.35
4.3.0 v8 4.5.103.35
4.2.6 v8 4.5.103.35
4.2.5 v8 4.5.103.35
4.2.4 v8 4.5.103.35
4.2.3 v8 4.5.103.35
4.2.2 v8 4.5.103.35
4.2.1 v8 4.5.103.35
4.2.0 v8 4.5.103.35
4.1.2 v8 4.5.103.35
4.1.1 v8 4.5.103.33
4.1.0 v8 4.5.103.33
4.0.0 v8 4.5.103.30
47% complete43% complete 		0.12.18
(these versions have identical results)
0.12.18 v8 3.28.71.20
29% complete22% complete 		0.10.48
(these versions have identical results)
0.10.48 v8 3.14.5.11
10% complete6% complete

optimisation

proper tail calls (tail call optimisation)

§direct recursion
?
function(){
"use strict"; return (function f(n){ if (n <= 0) { return "foo"; } return f(n - 1); }(1e6)) === "foo";
}
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function(){
"use strict"; return (function f(n){ if (n <= 0) { return "foo"; } return f(n - 1); }(1e6)) === "foo";
}
§mutual recursion
?
function(){
"use strict"; function f(n){ if (n <= 0) { return "foo"; } return g(n - 1); } function g(n){ if (n <= 0) { return "bar"; } return f(n - 1); } return f(1e6) === "foo" && f(1e6+1) === "bar";
}
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function(){
"use strict"; function f(n){ if (n <= 0) { return "foo"; } return g(n - 1); } function g(n){ if (n <= 0) { return "bar"; } return f(n - 1); } return f(1e6) === "foo" && f(1e6+1) === "bar";
}

syntax

default function parameters

§basic functionality
?
function(){
return (function (a = 1, b = 2) { return a === 3 && b === 2; }(3));
}
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function(){
return (function (a = 1, b = 2) { return a === 3 && b === 2; }(3));
}
§explicit undefined defers to the default
?
function(){
return (function (a = 1, b = 2) { return a === 1 && b === 3; }(undefined, 3));
}
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function(){
return (function (a = 1, b = 2) { return a === 1 && b === 3; }(undefined, 3));
}
§defaults can refer to previous params
?
function(){
return (function (a, b = a) { return b === 5; }(5));
}
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function(){
return (function (a, b = a) { return b === 5; }(5));
}
§arguments object interaction
?
function(){
return (function (a = "baz", b = "qux", c = "quux") { a = "corge"; // The arguments object is not mapped to the // parameters, even outside of strict mode. return arguments.length === 2 && arguments[0] === "foo" && arguments[1] === "bar"; }("foo", "bar"));
}
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function(){
return (function (a = "baz", b = "qux", c = "quux") { a = "corge"; // The arguments object is not mapped to the // parameters, even outside of strict mode. return arguments.length === 2 && arguments[0] === "foo" && arguments[1] === "bar"; }("foo", "bar"));
}
§temporal dead zone
?
function(){
return (function(x = 1) { try { eval("(function(a=a){}())"); return false; } catch(e) {} try { eval("(function(a=b,b){}())"); return false; } catch(e) {} return true; }());
}
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function(){
return (function(x = 1) { try { eval("(function(a=a){}())"); return false; } catch(e) {} try { eval("(function(a=b,b){}())"); return false; } catch(e) {} return true; }());
}
§separate scope
?
function(){
return (function(a=function(){ return typeof b === 'undefined'; }){ var b = 1; return a(); }());
}
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function(){
return (function(a=function(){ return typeof b === 'undefined'; }){ var b = 1; return a(); }());
}
§new Function() support
?
function(){
return new Function("a = 1", "b = 2", "return a === 3 && b === 2;" )(3);
}
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function(){
return new Function("a = 1", "b = 2", "return a === 3 && b === 2;" )(3);
}

rest parameters

§basic functionality
?
function(){
return (function (foo, ...args) { return args instanceof Array && args + "" === "bar,baz"; }("foo", "bar", "baz"));
}
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Error
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function(){
return (function (foo, ...args) { return args instanceof Array && args + "" === "bar,baz"; }("foo", "bar", "baz"));
}
§function 'length' property
?
function(){
return function(a, ...b){}.length === 1 && function(...c){}.length === 0;
}
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Error
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function(){
return function(a, ...b){}.length === 1 && function(...c){}.length === 0;
}
§arguments object interaction
?
function(){
return (function (foo, ...args) { foo = "qux"; // The arguments object is not mapped to the // parameters, even outside of strict mode. return arguments.length === 3 && arguments[0] === "foo" && arguments[1] === "bar" && arguments[2] === "baz"; }("foo", "bar", "baz"));
}
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function(){
return (function (foo, ...args) { foo = "qux"; // The arguments object is not mapped to the // parameters, even outside of strict mode. return arguments.length === 3 && arguments[0] === "foo" && arguments[1] === "bar" && arguments[2] === "baz"; }("foo", "bar", "baz"));
}
§can't be used in setters
?
function(){
return (function (...args) { try { eval("({set e(...args){}})"); } catch(e) { return true; } }());
}
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Flag
Error
Error
Error
Error
function(){
return (function (...args) { try { eval("({set e(...args){}})"); } catch(e) { return true; } }());
}
§new Function() support
?
function(){
return new Function("a", "...b", "return b instanceof Array && a+b === 'foobar,baz';" )('foo','bar','baz');
}
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Flag
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function(){
return new Function("a", "...b", "return b instanceof Array && a+b === 'foobar,baz';" )('foo','bar','baz');
}

spread syntax for iterable objects

§with arrays, in function calls
?
function(){
return Math.max(...[1, 2, 3]) === 3
}
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Error
Flag
Error
Error
Error
Error
function(){
return Math.max(...[1, 2, 3]) === 3
}
§with arrays, in array literals
?
function(){
return [...[1, 2, 3]][2] === 3;
}
Yes
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Error
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Error
function(){
return [...[1, 2, 3]][2] === 3;
}
§with sparse arrays, in function calls
?
function(){
var a = Array(...[,,]); return "0" in a && "1" in a && '' + a[0] + a[1] === "undefinedundefined";
}
Yes
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Error
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Error
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Error
function(){
var a = Array(...[,,]); return "0" in a && "1" in a && '' + a[0] + a[1] === "undefinedundefined";
}
§with sparse arrays, in array literals
?
function(){
var a = [...[,,]]; return "0" in a && "1" in a && '' + a[0] + a[1] === "undefinedundefined";
}
Yes
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Error
Flag
Error
Error
Error
Error
function(){
var a = [...[,,]]; return "0" in a && "1" in a && '' + a[0] + a[1] === "undefinedundefined";
}
§with strings, in function calls
?
function(){
return Math.max(..."1234") === 4;
}
Yes
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Error
Flag
Error
Error
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Error
function(){
return Math.max(..."1234") === 4;
}
§with strings, in array literals
?
function(){
return ["a", ..."bcd", "e"][3] === "d";
}
Yes
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Error
Flag
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Error
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Error
function(){
return ["a", ..."bcd", "e"][3] === "d";
}
§with astral plane strings, in function calls
?
function(){
return Array(..."𠮷𠮶")[0] === "𠮷";
}
Yes
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Error
Flag
Error
Error
Error
Error
function(){
return Array(..."𠮷𠮶")[0] === "𠮷";
}
§with astral plane strings, in array literals
?
function(){
return [..."𠮷𠮶"][0] === "𠮷";
}
Yes
Yes
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Error
Flag
Error
Error
Error
Error
function(){
return [..."𠮷𠮶"][0] === "𠮷";
}
§with generator instances, in calls
?
function(){
var iterable = (function*(){ yield 1; yield 2; yield 3; }()); return Math.max(...iterable) === 3;
}
Yes
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Error
Flag
Error
Error
Error
Error
function(){
var iterable = (function*(){ yield 1; yield 2; yield 3; }()); return Math.max(...iterable) === 3;
}
§with generator instances, in arrays
?
function(){
var iterable = (function*(){ yield "b"; yield "c"; yield "d"; }()); return ["a", ...iterable, "e"][3] === "d";
}
Yes
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Error
Flag
Error
Error
Error
Error
function(){
var iterable = (function*(){ yield "b"; yield "c"; yield "d"; }()); return ["a", ...iterable, "e"][3] === "d";
}
§with generic iterables, in calls
?
function(){
var iterable = global.__createIterableObject([1, 2, 3]); return Math.max(...iterable) === 3;
}
Yes
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Error
Flag
Error
Error
Error
Error
function(){
var iterable = global.__createIterableObject([1, 2, 3]); return Math.max(...iterable) === 3;
}
§with generic iterables, in arrays
?
function(){
var iterable = global.__createIterableObject(["b", "c", "d"]); return ["a", ...iterable, "e"][3] === "d";
}
Yes
Yes
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Error
Flag
Error
Error
Error
Error
function(){
var iterable = global.__createIterableObject(["b", "c", "d"]); return ["a", ...iterable, "e"][3] === "d";
}
§with instances of iterables, in calls
?
function(){
var iterable = global.__createIterableObject([1, 2, 3]); return Math.max(...Object.create(iterable)) === 3;
}
Yes
Yes
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Error
Flag
Error
Error
Error
Error
function(){
var iterable = global.__createIterableObject([1, 2, 3]); return Math.max(...Object.create(iterable)) === 3;
}
§with instances of iterables, in arrays
?
function(){
var iterable = global.__createIterableObject(["b", "c", "d"]); return ["a", ...Object.create(iterable), "e"][3] === "d";
}
Yes
Yes
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Error
Flag
Error
Error
Error
Error
function(){
var iterable = global.__createIterableObject(["b", "c", "d"]); return ["a", ...Object.create(iterable), "e"][3] === "d";
}
§spreading non-iterables is a runtime error
?
function(){
try { Math.max(...2); } catch(e) { return Math.max(...[1, 2, 3]) === 3; }
}
Yes
Yes
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Error
Flag
Error
Error
Error
Error
function(){
try { Math.max(...2); } catch(e) { return Math.max(...[1, 2, 3]) === 3; }
}

object literal extensions

§computed properties
?
function(){
var x = 'y'; return ({ [x]: 1 }).y === 1;
}
Yes
Yes
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Yes
Yes
Error
Error
Error
Error
function(){
var x = 'y'; return ({ [x]: 1 }).y === 1;
}
§shorthand properties
?
function(){
var a = 7, b = 8, c = {a,b}; return c.a === 7 && c.b === 8;
}
Yes
Yes
Yes
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Error
Error
Error
Error
function(){
var a = 7, b = 8, c = {a,b}; return c.a === 7 && c.b === 8;
}
§shorthand methods
?
function(){
return ({ y() { return 2; } }).y() === 2;
}
Yes
Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
function(){
return ({ y() { return 2; } }).y() === 2;
}
§string-keyed shorthand methods
?
function(){
return ({ "foo bar"() { return 4; } })["foo bar"]() === 4;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
function(){
return ({ "foo bar"() { return 4; } })["foo bar"]() === 4;
}
§computed shorthand methods
?
function(){
var x = 'y'; return ({ [x](){ return 1 } }).y() === 1;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
function(){
var x = 'y'; return ({ [x](){ return 1 } }).y() === 1;
}
§computed accessors
?
function(){
var x = 'y', valueSet, obj = { get [x] () { return 1 }, set [x] (value) { valueSet = value } }; obj.y = 'foo'; return obj.y === 1 && valueSet === 'foo';
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
function(){
var x = 'y', valueSet, obj = { get [x] () { return 1 }, set [x] (value) { valueSet = value } }; obj.y = 'foo'; return obj.y === 1 && valueSet === 'foo';
}

for..of loops

§with arrays
?
function(){
var arr = [5]; for (var item of arr) return item === 5;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
function(){
var arr = [5]; for (var item of arr) return item === 5;
}
§with sparse arrays
?
function(){
var arr = [,,]; var count = 0; for (var item of arr) count += (item === void undefined); return count === 2;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
function(){
var arr = [,,]; var count = 0; for (var item of arr) count += (item === void undefined); return count === 2;
}
§with strings
?
function(){
var str = ""; for (var item of "foo") str += item; return str === "foo";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
function(){
var str = ""; for (var item of "foo") str += item; return str === "foo";
}
§with astral plane strings
?
function(){
var str = ""; for (var item of "𠮷𠮶") str += item + " "; return str === "𠮷 𠮶 ";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
function(){
var str = ""; for (var item of "𠮷𠮶") str += item + " "; return str === "𠮷 𠮶 ";
}
§with generator instances
?
function(){
var result = ""; var iterable = (function*(){ yield 1; yield 2; yield 3; }()); for (var item of iterable) { result += item; } return result === "123";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Flag
Error
Error
function(){
var result = ""; var iterable = (function*(){ yield 1; yield 2; yield 3; }()); for (var item of iterable) { result += item; } return result === "123";
}
§with generic iterables
?
function(){
var result = ""; var iterable = global.__createIterableObject([1, 2, 3]); for (var item of iterable) { result += item; } return result === "123";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
function(){
var result = ""; var iterable = global.__createIterableObject([1, 2, 3]); for (var item of iterable) { result += item; } return result === "123";
}
§with instances of generic iterables
?
function(){
var result = ""; var iterable = global.__createIterableObject([1, 2, 3]); for (var item of Object.create(iterable)) { result += item; } return result === "123";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
function(){
var result = ""; var iterable = global.__createIterableObject([1, 2, 3]); for (var item of Object.create(iterable)) { result += item; } return result === "123";
}
§iterator closing, break
?
function(){
var closed = false; var iter = __createIterableObject([1, 2, 3], { 'return': function(){ closed = true; return {}; } }); for (var it of iter) break; return closed;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
No
Error
Error
function(){
var closed = false; var iter = __createIterableObject([1, 2, 3], { 'return': function(){ closed = true; return {}; } }); for (var it of iter) break; return closed;
}
§iterator closing, throw
?
function(){
var closed = false; var iter = __createIterableObject([1, 2, 3], { 'return': function(){ closed = true; return {}; } }); try { for (var it of iter) throw 0; } catch(e){} return closed;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
No
Error
Error
function(){
var closed = false; var iter = __createIterableObject([1, 2, 3], { 'return': function(){ closed = true; return {}; } }); try { for (var it of iter) throw 0; } catch(e){} return closed;
}

octal and binary literals

§octal literals
?
function(){
return 0o10 === 8 && 0O10 === 8;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Flag
Error
Error
function(){
return 0o10 === 8 && 0O10 === 8;
}
§binary literals
?
function(){
return 0b10 === 2 && 0B10 === 2;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Flag
Error
Error
function(){
return 0b10 === 2 && 0B10 === 2;
}
§octal supported by Number()
?
function(){
return Number('0o1') === 1;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
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Yes
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Yes
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Yes
Yes
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Yes
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Yes
Yes
Yes
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Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Flag
No
No
function(){
return Number('0o1') === 1;
}
§binary supported by Number()
?
function(){
return Number('0b1') === 1;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
Flag
No
No
function(){
return Number('0b1') === 1;
}

template literals

§basic functionality
?
function(){
var a = "ba", b = "QUX"; return `foo bar ${a + "z"} ${b.toLowerCase()}` === "foo bar\nbaz qux";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
function(){
var a = "ba", b = "QUX"; return `foo bar ${a + "z"} ${b.toLowerCase()}` === "foo bar\nbaz qux";
}
§toString conversion
?
function(){
var a = { toString: function() { return "foo"; }, valueOf: function() { return "bar"; } }; return `${a}` === "foo";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
function(){
var a = { toString: function() { return "foo"; }, valueOf: function() { return "bar"; } }; return `${a}` === "foo";
}
§tagged template literals
?
function(){
var called = false; function fn(parts, a, b) { called = true; return parts instanceof Array && parts[0] === "foo" && parts[1] === "bar\n" && parts.raw[0] === "foo" && parts.raw[1] === "bar\\n" && a === 123 && b === 456; } return fn `foo${123}bar\n${456}` && called;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
function(){
var called = false; function fn(parts, a, b) { called = true; return parts instanceof Array && parts[0] === "foo" && parts[1] === "bar\n" && parts.raw[0] === "foo" && parts.raw[1] === "bar\\n" && a === 123 && b === 456; } return fn `foo${123}bar\n${456}` && called;
}
§passed array is frozen
?
function(){
return (function(parts) { return Object.isFrozen(parts) && Object.isFrozen(parts.raw); }) `foo${0}bar${0}baz`;
}
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Error
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function(){
return (function(parts) { return Object.isFrozen(parts) && Object.isFrozen(parts.raw); }) `foo${0}bar${0}baz`;
}
§line break normalisation
?
function(){
var cr = eval("`x" + String.fromCharCode(13) + "y`"); var lf = eval("`x" + String.fromCharCode(10) + "y`"); var crlf = eval("`x" + String.fromCharCode(13,10) + "y`"); return cr.length === 3 && lf.length === 3 && crlf.length === 3 && cr[1] === lf[1] && lf[1] === crlf[1] && crlf[1] === '\n';
}
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Error
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function(){
var cr = eval("`x" + String.fromCharCode(13) + "y`"); var lf = eval("`x" + String.fromCharCode(10) + "y`"); var crlf = eval("`x" + String.fromCharCode(13,10) + "y`"); return cr.length === 3 && lf.length === 3 && crlf.length === 3 && cr[1] === lf[1] && lf[1] === crlf[1] && crlf[1] === '\n';
}
§TemplateStrings call site caching
?
function(){
// TemplateStrings caching was changed from per-contents to // per-call-site. // https://github.com/tc39/ecma262/pull/890 function strings(array) { return array; } function getStrings() { return strings`foo`; } var original = getStrings(); var other = strings`foo`; return original === getStrings() && original !== other;
}
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Error
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function(){
// TemplateStrings caching was changed from per-contents to // per-call-site. // https://github.com/tc39/ecma262/pull/890 function strings(array) { return array; } function getStrings() { return strings`foo`; } var original = getStrings(); var other = strings`foo`; return original === getStrings() && original !== other;
}
§TemplateStrings permanent caching
?
function(){
function strings(array) { return array; } function getStrings() { return strings`foo`; } var original = getStrings(); var newed = new getStrings(); return original === getStrings() && original === newed;
}
Yes
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Error
Error
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function(){
function strings(array) { return array; } function getStrings() { return strings`foo`; } var original = getStrings(); var newed = new getStrings(); return original === getStrings() && original === newed;
}

RegExp "y" and "u" flags

§"y" flag
?
function(){
var re = new RegExp('\\w', 'y'); re.exec('xy'); return (re.exec('xy')[0] === 'y');
}
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Error
function(){
var re = new RegExp('\\w', 'y'); re.exec('xy'); return (re.exec('xy')[0] === 'y');
}
§"y" flag, lastIndex
?
function(){
var re = new RegExp('yy', 'y'); re.lastIndex = 3; var result = re.exec('xxxyyxx')[0]; return result === 'yy' && re.lastIndex === 5;
}
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Error
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Error
function(){
var re = new RegExp('yy', 'y'); re.lastIndex = 3; var result = re.exec('xxxyyxx')[0]; return result === 'yy' && re.lastIndex === 5;
}
§"u" flag
?
function(){
return "𠮷".match(/^.$/u)[0].length === 2;
}
Yes
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Error
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function(){
return "𠮷".match(/^.$/u)[0].length === 2;
}
§"u" flag, non-BMP Unicode characters
?
function(){
return "𠮷x".match(/^.x$/u)[0].length === 3;
}
Yes
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Error
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function(){
return "𠮷x".match(/^.x$/u)[0].length === 3;
}
§"u" flag, Unicode code point escapes
?
function(){
return "𝌆".match(/\u{1d306}/u)[0].length === 2;
}
Yes
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Error
Error
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Error
function(){
return "𝌆".match(/\u{1d306}/u)[0].length === 2;
}
§"u" flag, case folding
?
function(){
return "ſ".match(/S/iu) && "S".match(/ſ/iu);
}
Yes
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Error
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Error
function(){
return "ſ".match(/S/iu) && "S".match(/ſ/iu);
}

destructuring, declarations

§with arrays
?
function(){
var [a, , [b], c] = [5, null, [6]]; return a === 5 && b === 6 && c === void undefined;
}
Yes
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Error
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function(){
var [a, , [b], c] = [5, null, [6]]; return a === 5 && b === 6 && c === void undefined;
}
§with sparse arrays
?
function(){
var [a, , b] = [,,,]; return a === void undefined && b === void undefined;
}
Yes
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Error
Error
Error
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Error
function(){
var [a, , b] = [,,,]; return a === void undefined && b === void undefined;
}
§with strings
?
function(){
var [a, b, c] = "ab"; return a === "a" && b === "b" && c === void undefined;
}
Yes
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Error
Error
Error
Error
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Error
Error
function(){
var [a, b, c] = "ab"; return a === "a" && b === "b" && c === void undefined;
}
§with astral plane strings
?
function(){
var [c] = "𠮷𠮶"; return c === "𠮷";
}
Yes
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Error
Error
Error
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Error
function(){
var [c] = "𠮷𠮶"; return c === "𠮷";
}
§with generator instances
?
function(){
var [a, b, c] = (function*(){ yield 1; yield 2; }()); return a === 1 && b === 2 && c === void undefined;
}
Yes
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Error
Error
Error
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Error
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function(){
var [a, b, c] = (function*(){ yield 1; yield 2; }()); return a === 1 && b === 2 && c === void undefined;
}
§with generic iterables
?
function(){
var [a, b, c] = global.__createIterableObject([1, 2]); return a === 1 && b === 2 && c === void undefined;
}
Yes
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Error
Error
Error
Error
Error
Error
Error
Error
function(){
var [a, b, c] = global.__createIterableObject([1, 2]); return a === 1 && b === 2 && c === void undefined;
}
§with instances of generic iterables
?
function(){
var [a, b, c] = Object.create(global.__createIterableObject([1, 2])); return a === 1 && b === 2 && c === void undefined;
}
Yes
Yes
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Error
Error
Error
Error
Error
Error
Error
Error
function(){
var [a, b, c] = Object.create(global.__createIterableObject([1, 2])); return a === 1 && b === 2 && c === void undefined;
}
§iterator closing
?
function(){
var closed = false; var iter = global.__createIterableObject([1, 2, 3], { 'return': function(){ closed = true; return {}; } }); var [a, b] = iter; return closed;
}
Yes
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No
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Error
Error
Error
Error
Error
Error
Error
Error
function(){
var closed = false; var iter = global.__createIterableObject([1, 2, 3], { 'return': function(){ closed = true; return {}; } }); var [a, b] = iter; return closed;
}
§trailing commas in iterable patterns
?
function(){
var [a,] = [1]; return a === 1;
}
Yes
Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var [a,] = [1]; return a === 1;
}
§with objects
?
function(){
var {c, x:d, e} = {c:7, x:8}; return c === 7 && d === 8 && e === void undefined;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var {c, x:d, e} = {c:7, x:8}; return c === 7 && d === 8 && e === void undefined;
}
§object destructuring with primitives
?
function(){
var {toFixed} = 2; var {slice} = ''; return toFixed === Number.prototype.toFixed && slice === String.prototype.slice;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var {toFixed} = 2; var {slice} = ''; return toFixed === Number.prototype.toFixed && slice === String.prototype.slice;
}
§trailing commas in object patterns
?
function(){
var {a,} = {a:1}; return a === 1;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var {a,} = {a:1}; return a === 1;
}
§throws on null and undefined
?
function(){
try { var {a} = null; return false; } catch(e) { if (!(e instanceof TypeError)) return false; } try { var {b} = void undefined; return false; } catch(e) { if (!(e instanceof TypeError)) return false; } return true;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
try { var {a} = null; return false; } catch(e) { if (!(e instanceof TypeError)) return false; } try { var {b} = void undefined; return false; } catch(e) { if (!(e instanceof TypeError)) return false; } return true;
}
§computed properties
?
function(){
var qux = "corge"; var { [qux]: grault } = { corge: "garply" }; return grault === "garply";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var qux = "corge"; var { [qux]: grault } = { corge: "garply" }; return grault === "garply";
}
§multiples in a single var statement
?
function(){
var [a,b] = [5,6], {c,d} = {c:7,d:8}; return a === 5 && b === 6 && c === 7 && d === 8;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var [a,b] = [5,6], {c,d} = {c:7,d:8}; return a === 5 && b === 6 && c === 7 && d === 8;
}
§nested
?
function(){
var [e, {x:f, g}] = [9, {x:10}]; var {h, x:[i]} = {h:11, x:[12]}; return e === 9 && f === 10 && g === void undefined && h === 11 && i === 12;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var [e, {x:f, g}] = [9, {x:10}]; var {h, x:[i]} = {h:11, x:[12]}; return e === 9 && f === 10 && g === void undefined && h === 11 && i === 12;
}
§in for-in loop heads
?
function(){
for(var [i, j, k] in { qux: 1 }) { return i === "q" && j === "u" && k === "x"; }
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
for(var [i, j, k] in { qux: 1 }) { return i === "q" && j === "u" && k === "x"; }
}
§in for-of loop heads
?
function(){
for(var [i, j, k] of [[1,2,3]]) { return i === 1 && j === 2 && k === 3; }
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
for(var [i, j, k] of [[1,2,3]]) { return i === 1 && j === 2 && k === 3; }
}
§in catch heads
?
function(){
try { throw [1,2]; } catch([i,j]) { try { throw { k: 3, l: 4 }; } catch({k, l}) { return i === 1 && j === 2 && k === 3 && l === 4; } }
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
try { throw [1,2]; } catch([i,j]) { try { throw { k: 3, l: 4 }; } catch({k, l}) { return i === 1 && j === 2 && k === 3 && l === 4; } }
}
§rest
?
function(){
var [a, ...b] = [3, 4, 5]; var [c, ...d] = [6]; return a === 3 && b instanceof Array && (b + "") === "4,5" && c === 6 && d instanceof Array && d.length === 0;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var [a, ...b] = [3, 4, 5]; var [c, ...d] = [6]; return a === 3 && b instanceof Array && (b + "") === "4,5" && c === 6 && d instanceof Array && d.length === 0;
}
§defaults
?
function(){
var {a = 1, b = 0, z:c = 3} = {b:2, z:undefined}; var [d = 0, e = 5, f = 6] = [4,,undefined]; return a === 1 && b === 2 && c === 3 && d === 4 && e === 5 && f === 6;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var {a = 1, b = 0, z:c = 3} = {b:2, z:undefined}; var [d = 0, e = 5, f = 6] = [4,,undefined]; return a === 1 && b === 2 && c === 3 && d === 4 && e === 5 && f === 6;
}
§defaults, let temporal dead zone
?
function(){
var {a, b = 2} = {a:1}; try { eval("let {c = c} = {};"); return false; } catch(e){} try { eval("let {c = d, d} = {d:1};"); return false; } catch(e){} return a === 1 && b === 2;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
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Yes
Yes
Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var {a, b = 2} = {a:1}; try { eval("let {c = c} = {};"); return false; } catch(e){} try { eval("let {c = d, d} = {d:1};"); return false; } catch(e){} return a === 1 && b === 2;
}

destructuring, assignment

§with arrays
?
function(){
var a,b,c; [a, , [b], c] = [5, null, [6]]; return a === 5 && b === 6 && c === void undefined;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a,b,c; [a, , [b], c] = [5, null, [6]]; return a === 5 && b === 6 && c === void undefined;
}
§with sparse arrays
?
function(){
var a, b; [a, , b] = [,,,]; return a === void undefined && b === void undefined;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a, b; [a, , b] = [,,,]; return a === void undefined && b === void undefined;
}
§with strings
?
function(){
var a,b,c; [a, b, c] = "ab"; return a === "a" && b === "b" && c === void undefined;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a,b,c; [a, b, c] = "ab"; return a === "a" && b === "b" && c === void undefined;
}
§with astral plane strings
?
function(){
var c; [c] = "𠮷𠮶"; return c === "𠮷";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var c; [c] = "𠮷𠮶"; return c === "𠮷";
}
§with generator instances
?
function(){
var a,b,c; [a, b, c] = (function*(){ yield 1; yield 2; }()); return a === 1 && b === 2 && c === void undefined;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a,b,c; [a, b, c] = (function*(){ yield 1; yield 2; }()); return a === 1 && b === 2 && c === void undefined;
}
§with generic iterables
?
function(){
var a,b,c; [a, b, c] = global.__createIterableObject([1, 2]); return a === 1 && b === 2 && c === void undefined;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a,b,c; [a, b, c] = global.__createIterableObject([1, 2]); return a === 1 && b === 2 && c === void undefined;
}
§with instances of generic iterables
?
function(){
var a,b,c; [a, b, c] = Object.create(global.__createIterableObject([1, 2])); return a === 1 && b === 2 && c === void undefined;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a,b,c; [a, b, c] = Object.create(global.__createIterableObject([1, 2])); return a === 1 && b === 2 && c === void undefined;
}
§iterator closing
?
function(){
var closed = false; var iter = global.__createIterableObject([1, 2, 3], { 'return': function(){ closed = true; return {}; } }); var a,b; [a, b] = iter; return closed;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
No
No
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var closed = false; var iter = global.__createIterableObject([1, 2, 3], { 'return': function(){ closed = true; return {}; } }); var a,b; [a, b] = iter; return closed;
}
§iterable destructuring expression
?
function(){
var a, b, iterable = [1,2]; return ([a, b] = iterable) === iterable;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a, b, iterable = [1,2]; return ([a, b] = iterable) === iterable;
}
§chained iterable destructuring
?
function(){
var a,b,c,d; [a,b] = [c,d] = [1,2]; return a === 1 && b === 2 && c === 1 && d === 2;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
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Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a,b,c,d; [a,b] = [c,d] = [1,2]; return a === 1 && b === 2 && c === 1 && d === 2;
}
§trailing commas in iterable patterns
?
function(){
var a; [a,] = [1]; return a === 1;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a; [a,] = [1]; return a === 1;
}
§with objects
?
function(){
var c,d,e; ({c, x:d, e} = {c:7, x:8}); return c === 7 && d === 8 && e === void undefined;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var c,d,e; ({c, x:d, e} = {c:7, x:8}); return c === 7 && d === 8 && e === void undefined;
}
§object destructuring with primitives
?
function(){
var toFixed, slice; ({toFixed} = 2); ({slice} = ''); return toFixed === Number.prototype.toFixed && slice === String.prototype.slice;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var toFixed, slice; ({toFixed} = 2); ({slice} = ''); return toFixed === Number.prototype.toFixed && slice === String.prototype.slice;
}
§trailing commas in object patterns
?
function(){
var a; ({a,} = {a:1}); return a === 1;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a; ({a,} = {a:1}); return a === 1;
}
§object destructuring expression
?
function(){
var a, b, obj = { a:1, b:2 }; return ({a,b} = obj) === obj;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a, b, obj = { a:1, b:2 }; return ({a,b} = obj) === obj;
}
§parenthesised left-hand-side is a syntax error
?
function(){
var a, b; ({a,b} = {a:1,b:2}); try { eval("({a,b}) = {a:3,b:4};"); } catch(e) { return a === 1 && b === 2; }
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a, b; ({a,b} = {a:1,b:2}); try { eval("({a,b}) = {a:3,b:4};"); } catch(e) { return a === 1 && b === 2; }
}
§chained object destructuring
?
function(){
var a,b,c,d; ({a,b} = {c,d} = {a:1,b:2,c:3,d:4}); return a === 1 && b === 2 && c === 3 && d === 4;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
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Yes
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Yes
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Yes
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Yes
Yes
Yes
Yes
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Yes
Yes
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Yes
Yes
Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a,b,c,d; ({a,b} = {c,d} = {a:1,b:2,c:3,d:4}); return a === 1 && b === 2 && c === 3 && d === 4;
}
§throws on null and undefined
?
function(){
var a,b; try { ({a} = null); return false; } catch(e) { if (!(e instanceof TypeError)) return false; } try { ({b} = void undefined); return false; } catch(e) { if (!(e instanceof TypeError)) return false; } return true;
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
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Yes
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Yes
Yes
Yes
Yes
Yes
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Yes
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Yes
Yes
Yes
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Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Error
Error
Error
Error
Error
Error
Error
Error
function(){
var a,b; try { ({a} = null); return false; } catch(e) { if (!(e instanceof TypeError)) return false; } try { ({b} = void undefined); return false; } catch(e) { if (!(e instanceof TypeError)) return false; } return true;
}
§computed properties
?
function(){
var grault, qux = "corge"; ({ [qux]: grault } = { corge: "garply" }); return grault === "garply";
}
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes