ECMAScript proposal for offset information for capturing groups in regular expressions.
ECMAScript allows to match a regular expression against a string, which returns the matched chunks. For further processing you sometimes additionally require the offsets of the capturing groups of those matches, which are not exposed by the current APIs.
The array returned by RegExp.prototype.exec() should be extended by an offsets property, which represents an array of the start indices of the match and all the captured groups.
let matches = /a(b(c))/.exec("abcabc");Then matches will contain this:
{
0: "abc",
1: "bc",
2: "c",
index: 0,
input: "abcabc",
offsets: [
0,
1
2
]
}let matches = /a(b(c))/g.exec("abcabc");Then matches will contain this when executed the first time:
{
0: "abc",
1: "bc",
2: "c",
index: 0,
input: "abcabc",
offsets: [
0,
1
2
]
}And this when executed the second time:
{
0: "abc",
1: "bc",
2: "c",
index: 3,
input: "abcabc",
offsets: [
3,
4
5
]
}