balanced-match
Match balanced string pairs, like { and } or <b> and
</b>. Supports regular expressions as well!
Example
Get the first matching pair of braces:
import { balanced } from 'balanced-match'
console.log(balanced('{', '}', 'pre{in{nested}}post'))
console.log(balanced('{', '}', 'pre{first}between{second}post'))
console.log(
balanced(/\s+\{\s+/, /\s+\}\s+/, 'pre { in{nest} } post'),
)
The matches are:
$ node example.js
{ start: 3, end: 14, pre: 'pre', body: 'in{nested}', post: 'post' }
{ start: 3,
end: 9,
pre: 'pre',
body: 'first',
post: 'between{second}post' }
{ start: 3, end: 17, pre: 'pre', body: 'in{nest}', post: 'post' }
API
const m = balanced(a, b, str)
For the first non-nested matching pair of a and b in str, return an
object with those keys:
- start the index of the first match of
a - end the index of the matching
b - pre the preamble,
aandbnot included - body the match,
aandbnot included - post the postscript,
aandbnot included
If there's no match, undefined will be returned.
If the str contains more a than b / there are unmatched pairs, the first match that was closed will be used. For example, {{a} will match ['{', 'a', ''] and {a}} will match ['', 'a', '}'].
const r = balanced.range(a, b, str)
For the first non-nested matching pair of a and b in str, return an
array with indexes: [ <a index>, <b index> ].
If there's no match, undefined will be returned.
If the str contains more a than b / there are unmatched pairs, the first match that was closed will be used. For example, {{a} will match [ 1, 3 ] and {a}} will match [0, 2].