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"status": {
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"standard_track": true,
"deprecated": false
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"safari_ios": "mirror",
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"webview_android": "mirror"
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"standard_track": true,
"deprecated": false
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}
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"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-block",
"tags": [
"web-features:snapshot:ecmascript-1"
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"support": {
"chrome": {
"version_added": "1"
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"chrome_android": "mirror",
"deno": {
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"edge": {
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"firefox": {
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"ie": {
"version_added": "11"
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"safari": {
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"safari_ios": "mirror",
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"webview_android": "mirror"
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"experimental": false,
"standard_track": true,
"deprecated": false
}
}
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"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-break-statement",
"tags": [
"web-features:snapshot:ecmascript-1"
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"support": {
"chrome": {
"version_added": "1"
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"chrome_android": "mirror",
"deno": {
"version_added": "1.0"
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"edge": {
"version_added": "12"
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"firefox": {
"version_added": "1"
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"ie": {
"version_added": "3"
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"safari": {
"version_added": "1"
},
"safari_ios": "mirror",
"samsunginternet_android": "mirror",
"webview_android": "mirror"
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"experimental": false,
"standard_track": true,
"deprecated": false
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"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-functions-and-classes.html#sec-class-definitions",
"tags": [
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"web-features:snapshot:ecmascript-2015"
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"chrome": [
{
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},
{
"version_added": "42",
"version_removed": "49",
"notes": "Strict mode is required."
}
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"edge": {
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"ie": {
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"oculus": "mirror",
"opera": "mirror",
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"version_added": "10.1"
},
"safari_ios": "mirror",
"samsunginternet_android": "mirror",
"webview_android": "mirror"
},
"status": {
"experimental": false,
"standard_track": true,
"deprecated": false
}
}
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"mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/const",
"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-let-and-const-declarations",
"tags": [
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},
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"edge": {
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"notes": [
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"oculus": "mirror",
"opera": {
"version_added": "9"
},
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"version_added": "5.1"
},
"safari_ios": "mirror",
"samsunginternet_android": "mirror",
"webview_android": "mirror"
},
"status": {
"experimental": false,
"standard_track": true,
"deprecated": false
}
}
},
"continue": {
"__compat": {
"mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/continue",
"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-continue-statement",
"tags": [
"web-features:snapshot:ecmascript-1"
],
"support": {
"chrome": {
"version_added": "1"
},
"chrome_android": "mirror",
"deno": {
"version_added": "1.0"
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"edge": {
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"firefox": {
"version_added": "1"
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"ie": {
"version_added": "3"
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"opera": {
"version_added": "4"
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},
"safari": {
"version_added": "1"
},
"safari_ios": "mirror",
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"webview_android": "mirror"
},
"status": {
"experimental": false,
"standard_track": true,
"deprecated": false
}
}
},
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"__compat": {
"mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/debugger",
"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-debugger-statement",
"support": {
"chrome": {
"version_added": "5"
},
"chrome_android": "mirror",
"deno": {
"version_added": "1.0"
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"edge": {
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"safari": {
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},
"safari_ios": "mirror",
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"webview_android": "mirror"
},
"status": {
"experimental": false,
"standard_track": true,
"deprecated": false
}
}
},
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"description": "do...while",
"mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/do...while",
"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-do-while-statement",
"tags": [
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],
"support": {
"chrome": {
"version_added": "1"
},
"chrome_android": "mirror",
"deno": {
"version_added": "1.0"
},
"edge": {
"version_added": "12"
},
"firefox": {
"version_added": "1"
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"firefox_android": "mirror",
"ie": {
"version_added": "4"
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},
"oculus": "mirror",
"opera": {
"version_added": "4"
},
"opera_android": {
"version_added": "10.1"
},
"safari": {
"version_added": "1"
},
"safari_ios": "mirror",
"samsunginternet_android": "mirror",
"webview_android": "mirror"
},
"status": {
"experimental": false,
"standard_track": true,
"deprecated": false
}
}
},
"empty": {
"__compat": {
"description": "Empty statement (;)",
"mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/Empty",
"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-empty-statement",
"tags": [
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],
"support": {
"chrome": {
"version_added": "3"
},
"chrome_android": "mirror",
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"edge": {
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},
"safari": {
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},
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"webview_android": "mirror"
},
"status": {
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"standard_track": true,
"deprecated": false
}
}
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"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-scripts-and-modules.html#sec-exports",
"tags": [
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],
"support": {
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},
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"firefox": {
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"notes": "Modules must either have a filename ending in .mjs, or the nearest parent package.json file must contain \"type\": \"module\". See Node's ECMAScript Modules documentation for more details."
},
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"webview_android": "mirror"
},
"status": {
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"standard_track": true,
"deprecated": false
}
},
"default": {
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"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-scripts-and-modules.html#sec-exports",
"tags": [
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],
"support": {
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"deno": {
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"firefox_android": "mirror",
"ie": {
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"notes": "Modules must either have a filename ending in .mjs, or the nearest parent package.json file must contain \"type\": \"module\". See Node's ECMAScript Modules documentation for more details."
},
"oculus": "mirror",
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},
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"webview_android": "mirror"
},
"status": {
"experimental": false,
"standard_track": true,
"deprecated": false
}
}
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"namespace": {
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"description": "export * as namespace",
"mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/export",
"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-scripts-and-modules.html#sec-exports",
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"chrome": {
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},
"chrome_android": "mirror",
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},
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"ie": {
"version_added": false
},
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"notes": "Modules must either have a filename ending in .mjs, or the nearest parent package.json file must contain \"type\": \"module\". See Node's ECMAScript Modules documentation for more details."
},
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"status": {
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"standard_track": true,
"deprecated": false
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}
}
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"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-for-statement",
"tags": [
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],
"support": {
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},
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},
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"webview_android": "mirror"
},
"status": {
"experimental": false,
"standard_track": true,
"deprecated": false
}
}
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"mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/for-await...of",
"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-for-in-and-for-of-statements",
"tags": [
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],
"support": {
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},
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"webview_android": "mirror"
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"status": {
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}
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"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-for-in-and-for-of-statements",
"tags": [
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"support": {
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"status": {
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"standard_track": true,
"deprecated": false
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}
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"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-statements-and-declarations.html#sec-for-in-and-for-of-statements",
"tags": [
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"support": {
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},
"chrome_android": "mirror",
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"firefox": {
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"notes": "Before Firefox 51, using the for...of loop construct with the const keyword threw a SyntaxError (\"missing = in const declaration\")."
},
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"status": {
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"deprecated": false
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"async_iterators": {
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"description": "async iterators",
"tags": [
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"support": {
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},
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"webview_android": "mirror"
},
"status": {
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"deprecated": false
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}
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"support": {
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},
"chrome_android": "mirror",
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"status": {
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"standard_track": true,
"deprecated": false
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"function": {
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"mdn_url": "https://developer.mozilla.org/docs/Web/JavaScript/Reference/Statements/function",
"spec_url": "https://tc39.es/ecma262/multipage/ecmascript-language-functions-and-classes.html#sec-function-definitions",
"tags": [
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"support": {
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