The source
accessor property of RegExp
instances returns a string containing the source text of this regular expression, without the two forward slashes on both sides or any flags.
The source
accessor property of RegExp
instances returns a string containing the source text of this regular expression, without the two forward slashes on both sides or any flags.
Conceptually, the source
property is the text between the two forward slashes in the regular expression literal. The language requires the returned string to be properly escaped, so that when the source
is concatenated with a forward slash on both ends, it would form a parsable regex literal. For example, for new RegExp("/")
, the source
is \\/
, because if it generates /
, the resulting literal becomes ///
, which is a line comment. Similarly, all line terminators will be escaped because line terminator characters would break up the regex literal. There's no requirement for other characters, as long as the result is parsable. For empty regular expressions, the string (?:)
is returned.
const regex = /fooBar/gi; console.log(regex.source); // "fooBar", doesn't contain /.../ and "gi".
new RegExp().source; // "(?:)" new RegExp("\n").source === "\\n"; // true, starting with ES5
Desktop | Mobile | Server | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | Deno | Node.js | ||
source |
1 | 12 | 1 | 5 | 1 | 18 | 4 | 10.1 | 1 | 1.0 | 4.4 | 1.0 | 0.10.0 | |
empty_regex_string |
6 | 12 | 38 | 15 | 5 | 18 | 38 | 14 | 4.2 | 1.0 | ≤37 | 1.0 | 0.10.0 | |
escaping |
73 | 12 | 38 | 60 | 6 | 73 | 38 | 52 | 6 | 11.0 | 73 | 1.0 | 12.0.0 | |
prototype_accessor |
48 | 12 | 41 | 35 | 1.3 | 48 | 41 | 35 | 1 | 5.0 | 48 | 1.0 | 6.0.0 |
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https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp/source