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} }, "status": { "experimental": false, "standard_track": true, "deprecated": false } }, "IteratorResult_object": { "__compat": { "description": "IteratorResult object instead of throwing", "support": { "chrome": { "version_added": "49" }, "chrome_android": { "version_added": true }, "edge": { "version_added": "13" }, "edge_mobile": { "version_added": true }, "firefox": { "version_added": "29" }, "firefox_android": { "version_added": "29" }, "ie": { "version_added": false }, "nodejs": { "version_added": true }, "opera": { "version_added": true }, "opera_android": { "version_added": true }, "safari": { "version_added": true }, "safari_ios": { "version_added": true }, "samsunginternet_android": { "version_added": true }, "webview_android": { "version_added": true } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "not_constructable_with_new": { "__compat": { "description": "Not constructable with new (ES2016)", "support": { "chrome": { "version_added": true }, "chrome_android": { "version_added": true }, "edge": { "version_added": null }, "edge_mobile": { "version_added": null }, "firefox": { "version_added": "43" }, "firefox_android": { "version_added": "43" }, "ie": { "version_added": false }, "nodejs": { "version_added": true }, "opera": { "version_added": true }, "opera_android": { "version_added": true }, "safari": { "version_added": "10" }, "safari_ios": { "version_added": "10" }, "samsunginternet_android": { "version_added": true }, "webview_android": { "version_added": true } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "trailing_comma_in_parameters": { "__compat": { "description": "Trailing comma in parameters", "support": { "chrome": { "version_added": null }, "chrome_android": { "version_added": null }, "edge": { "version_added": null }, "edge_mobile": { "version_added": null }, "firefox": { "version_added": "52" }, "firefox_android": { "version_added": "52" }, "ie": { "version_added": null }, "nodejs": { "version_added": "8.0.0" }, "opera": { "version_added": true }, "opera_android": { "version_added": null }, "safari": { "version_added": null }, "safari_ios": { "version_added": null }, "samsunginternet_android": { "version_added": null }, "webview_android": { "version_added": null } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } } }, "if_else": { "__compat": { "description": "if...else", "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/if...else", "spec_url": "https://tc39.github.io/ecma262/#sec-if-statement", "support": { "chrome": { "version_added": true }, "chrome_android": { "version_added": true }, "edge": { "version_added": true }, "edge_mobile": { "version_added": true }, "firefox": { "version_added": "1" }, "firefox_android": { "version_added": "4" }, "ie": { "version_added": true }, "nodejs": { "version_added": true }, "opera": { "version_added": true }, "opera_android": { "version_added": true }, "safari": { "version_added": true }, "safari_ios": { "version_added": true }, "samsunginternet_android": { "version_added": true }, "webview_android": { "version_added": true } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "import": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/import", "spec_url": [ "https://github.com/tc39/proposal-dynamic-import/#import", "https://tc39.github.io/ecma262/#sec-imports" ], "support": { "chrome": { "version_added": "61" }, "chrome_android": { "version_added": "61" }, "edge": [ { "version_added": "16" }, { "version_added": "15", "flags": [ { "name": "Experimental JavaScript Features", "type": "preference" } ] } ], "edge_mobile": { "version_added": true }, "firefox": [ { "version_added": "60" }, { "version_added": "54", "version_removed": "60", "flags": [ { "name": "dom.moduleScripts.enabled", "type": "preference" } ] } ], "firefox_android": [ { "version_added": "60" }, { "version_added": "54", "version_removed": "60", "flags": [ { "name": "dom.moduleScripts.enabled", "type": "preference" } ] } ], "ie": { "version_added": false }, "nodejs": { "version_added": "8.5.0", "flags": [ { "name": "--experimental-modules", "type": "runtime_flag" } ], "notes": "files must have suffix .mjs, not .js" }, "opera": { "version_added": "47" }, "opera_android": { "version_added": "47" }, "safari": { "version_added": "10.1" }, "safari_ios": { "version_added": "10.1" }, "samsunginternet_android": { "version_added": false }, "webview_android": { "version_added": "61" } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } }, "dynamic_import": { "__compat": { "description": "Dynamic import", "support": { "chrome": { "version_added": "63" }, "chrome_android": { "version_added": "63" }, "edge": { "version_added": false, "notes": "See development status." }, "edge_mobile": { "version_added": false }, "firefox": { "version_added": "66", "flags": [ { "name": "javascript.options.dynamicImport", "type": "preference", "value_to_set": "true" } ], "notes": "See bug 1517546. This flag is enabled by default on nightly builds from Nightly 67. See bug 1522491." }, "firefox_android": { "version_added": "66", "flags": [ { "name": "javascript.options.dynamicImport", "type": "preference", "value_to_set": "true" } ], "notes": "See bug 1517546. This flag is enabled by default on nightly builds from Nightly 67. See bug 1522491." }, "ie": { "version_added": false }, "nodejs": { "version_added": null }, "opera": { "version_added": "50" }, "opera_android": { "version_added": "50" }, "safari": { "version_added": "11.1" }, "safari_ios": { "version_added": "11.1" }, "samsunginternet_android": { "version_added": null }, "webview_android": { "version_added": "63" } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } } }, "import_meta": { "__compat": { "description": "import.meta", "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/import.meta", "spec_url": [ "https://github.com/tc39/proposal-import-meta/#importmeta", "https://html.spec.whatwg.org/multipage/webappapis.html#hostgetimportmetaproperties" ], "support": { "chrome": { "version_added": "64" }, "chrome_android": { "version_added": "64" }, "firefox": { "version_added": "62" }, "firefox_android": { "version_added": "62" }, "ie": { "version_added": false }, "opera": { "version_added": "51" }, "opera_android": { "version_added": "51" }, "samsunginternet_android": { "version_added": false }, "webview_android": { "version_added": "64" } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "label": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/label", "spec_url": "https://tc39.github.io/ecma262/#sec-labelled-statements", "support": { "chrome": { "version_added": true }, "chrome_android": { "version_added": true }, "edge": { "version_added": true }, "edge_mobile": { "version_added": true }, "firefox": { "version_added": "1" }, "firefox_android": { "version_added": "4" }, "ie": { "version_added": true }, "nodejs": { "version_added": true }, "opera": { "version_added": true }, "opera_android": { "version_added": true }, "safari": { "version_added": true }, "safari_ios": { "version_added": true }, "samsunginternet_android": { "version_added": true }, "webview_android": { "version_added": true } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "let": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/let", "spec_url": "https://tc39.github.io/ecma262/#sec-let-and-const-declarations", "support": { "chrome": [ { "version_added": "49" }, { "version_added": "48", "version_removed": "49", "flags": [ { "type": "preference", "name": "Enable Experimental JavaScript Features" } ], "notes": "Support outside of strict mode." }, { "version_added": "41", "version_removed": "49", "partial_implementation": true, "notes": "Strict mode is required." } ], "chrome_android": [ { "version_added": "49" }, { "version_added": "48", "version_removed": "49", "flags": [ { "type": "preference", "name": "Enable Experimental JavaScript Features" } ], "notes": "Support outside of strict mode." }, { "version_added": "41", "version_removed": "49", "partial_implementation": true, "notes": "Strict 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{ "version_added": "17" }, "opera_android": { "version_added": "17" }, "safari": { "version_added": "10" }, "safari_ios": { "version_added": "10" }, "samsunginternet_android": { "version_added": "4.0" }, "webview_android": [ { "version_added": "49" }, { "version_added": "41", "version_removed": "49", "partial_implementation": true, "notes": "Strict mode is required." } ] }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "return": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/return", "spec_url": "https://tc39.github.io/ecma262/#sec-return-statement", "support": { "chrome": { "version_added": true }, "chrome_android": { "version_added": true }, "edge": { "version_added": true }, "edge_mobile": { "version_added": true }, "firefox": { "version_added": "1" }, "firefox_android": { "version_added": "4" }, "ie": { "version_added": true }, "nodejs": { "version_added": true }, "opera": { "version_added": true }, "opera_android": { "version_added": true }, "safari": { "version_added": true }, "safari_ios": { "version_added": true }, "samsunginternet_android": { "version_added": true }, "webview_android": { "version_added": true } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "switch": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/switch", "spec_url": "https://tc39.github.io/ecma262/#sec-switch-statement", "support": { "chrome": { "version_added": true }, "chrome_android": { "version_added": true }, "edge": { "version_added": true }, "edge_mobile": { "version_added": true }, "firefox": { "version_added": "1" }, "firefox_android": { "version_added": "4" }, "ie": { "version_added": true }, "nodejs": { "version_added": true }, "opera": { "version_added": true }, "opera_android": { "version_added": true }, "safari": { "version_added": true }, "safari_ios": { "version_added": true }, "samsunginternet_android": { "version_added": true }, "webview_android": { "version_added": true } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "throw": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/throw", "spec_url": "https://tc39.github.io/ecma262/#sec-throw-statement", "support": { "chrome": { "version_added": true }, "chrome_android": { "version_added": true }, "edge": { "version_added": true }, "edge_mobile": { "version_added": true }, "firefox": { "version_added": "1" }, "firefox_android": { "version_added": "4" }, "ie": { "version_added": true }, "nodejs": { "version_added": true }, "opera": { "version_added": true }, "opera_android": { "version_added": true }, "safari": { "version_added": true }, "safari_ios": { "version_added": true }, "samsunginternet_android": { "version_added": true }, "webview_android": { "version_added": true } }, "status": { "experimental": false, 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"Conditional clauses", "support": { "chrome": { "version_added": false }, "chrome_android": { "version_added": false }, "edge": { "version_added": false }, "edge_mobile": { "version_added": false }, "firefox": { "version_added": "1", "version_removed": "59" }, "firefox_android": { "version_added": "4", "version_removed": "59" }, "ie": { "version_added": false }, "nodejs": { "version_added": false }, "opera": { "version_added": false }, "opera_android": { "version_added": false }, "safari": { "version_added": false }, "safari_ios": { "version_added": false }, "samsunginternet_android": { "version_added": false }, "webview_android": { "version_added": false } }, "status": { "experimental": false, "standard_track": false, "deprecated": true } } }, "optional_catch_binding": { "__compat": { "description": "Optional catch binding", "support": { "chrome": { "version_added": "66" }, "chrome_android": { "version_added": "66" }, "edge": { "version_added": false }, "edge_mobile": { "version_added": false }, "firefox": { "version_added": "58" }, "firefox_android": { "version_added": "58" }, "ie": { "version_added": false }, "nodejs": { "version_added": false }, "opera": { "version_added": "53" }, "opera_android": { "version_added": "53" }, "safari": { "version_added": false }, "safari_ios": { "version_added": false }, "samsunginternet_android": { "version_added": false }, "webview_android": { "version_added": "66" } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } } }, "var": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/var", "spec_url": "https://tc39.github.io/ecma262/#sec-variable-statement", "support": { "chrome": { "version_added": true }, "chrome_android": { "version_added": true }, "edge": { "version_added": true }, "edge_mobile": { "version_added": true }, "firefox": { "version_added": "1" }, "firefox_android": { "version_added": "4" }, "ie": { "version_added": true 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"version_added": true } }, "status": { "experimental": false, "standard_track": true, "deprecated": true } } } } } }