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"version_added": "8", "flags": [ { "name": "--experimental-modules", "type": "runtime_flag" } ] }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } }, "dynamic_import": { "__compat": { "description": "Dynamic import", "support": { "webview_android": { "version_added": "63" }, "chrome": { "version_added": "63" }, "chrome_android": { "version_added": "63" }, "edge": { "version_added": null }, "edge_mobile": { "version_added": null }, "firefox": { "version_added": null }, "firefox_android": { "version_added": null }, "ie": { "version_added": null }, "nodejs": { "version_added": null }, "opera": { "version_added": "50" }, "opera_android": { "version_added": "50" }, "safari": { "version_added": null }, "safari_ios": { "version_added": null }, "samsunginternet_android": { "version_added": null } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } } }, "label": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/label", "support": { "webview_android": { "version_added": true }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "let": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/let", "support": { "webview_android": [ { "version_added": "49" }, { "version_added": "41", "version_removed": "49", "partial_implementation": true, "notes": "Strict mode is required." } ], "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 mode is required." } ], "edge": { "version_added": "12" }, "edge_mobile": { "version_added": "12" }, "firefox": { "version_added": "44", "notes": [ "Prior to Firefox 44, let is only available to code blocks in HTML wrapped in a <script type=\"application/javascript;version=1.7\"> block (or higher version) and has different semantics (e.g. no temporal dead zone).", "Prior to Firefox 46, a TypeError is thrown on redeclaration instead of a SyntaxError.", "Firefox 54 adds support of let in workers." ] }, "firefox_android": { "version_added": "44", "notes": [ "Prior to Firefox 44, let is only available to code blocks in HTML wrapped in a <script type=\"application/javascript;version=1.7\"> block (or higher version) and has different semantics (e.g. no temporal dead zone).", "Prior to Firefox 46, a TypeError is thrown on redeclaration instead of a SyntaxError.", "Firefox 54 adds support of let in workers." ] }, "ie": { "version_added": "11" }, "nodejs": { "version_added": true }, "opera": { "version_added": "17" }, "opera_android": { "version_added": "17" }, "safari": { "version_added": "10" }, "safari_ios": { "version_added": "10" }, "samsunginternet_android": { "version_added": "4.0" } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "return": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/return", "support": { "webview_android": { "version_added": true }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "switch": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/switch", "support": { "webview_android": { "version_added": true }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "throw": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/throw", "support": { "webview_android": { "version_added": true }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "try_catch": { "__compat": { "description": "try...catch", "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/try...catch", "support": { "webview_android": { "version_added": true }, "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": "6" }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } }, "conditional_clauses": { "__compat": { "description": "Conditional clauses", "support": { "webview_android": { "version_added": false }, "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 } }, "status": { "experimental": false, "standard_track": false, "deprecated": true } } }, "optional_catch_binding": { "__compat": { "description": "Optional catch binding", "support": { "webview_android": { "version_added": "66" }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } } }, "var": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/var", "support": { "webview_android": { "version_added": true }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "while": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/while", "support": { "webview_android": { "version_added": true }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": false } } }, "with": { "__compat": { "mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/with", "support": { "webview_android": { "version_added": true }, "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 } }, "status": { "experimental": false, "standard_track": true, "deprecated": true } } } } } }