Positive look behind in JavaScript regular expression

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Lookbehind assertions were recently finalised for JavaScript and will be in the next publication of the ECMA-262 specification. They are supported in Chrome 66 (Opera 53), but no other major browsers at the time of writing (caniuse).

var str="Text:"How secure is my information?"",
    reg = /(?<=Text:")[^"]+(?=")/;

str.match(reg)[0];
// -> How secure is my information?

Older browsers do not support lookbehind in JavaScript regular expression. You have to use capturing parenthesis for expressions like this one instead:

var str="Text:"How secure is my information?"",
    reg = /Text:"([^"]+)"/;

str.match(reg)[1];
// -> How secure is my information?

This will not cover all the lookbehind assertion use cases, however.

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