2 module.exports = balanced;
3 function balanced(a, b, str) {
4 if (a instanceof RegExp) a = maybeMatch(a, str);
5 if (b instanceof RegExp) b = maybeMatch(b, str);
7 var r = range(a, b, str);
12 pre: str.slice(0, r[0]),
13 body: str.slice(r[0] + a.length, r[1]),
14 post: str.slice(r[1] + b.length)
18 function maybeMatch(reg, str) {
19 var m = str.match(reg);
20 return m ? m[0] : null;
23 balanced.range = range;
24 function range(a, b, str) {
25 var begs, beg, left, right, result;
26 var ai = str.indexOf(a);
27 var bi = str.indexOf(b, ai + 1);
30 if (ai >= 0 && bi > 0) {
37 while (i >= 0 && !result) {
40 ai = str.indexOf(a, i + 1);
41 } else if (begs.length == 1) {
42 result = [ begs.pop(), bi ];
50 bi = str.indexOf(b, i + 1);
53 i = ai < bi && ai >= 0 ? ai : bi;
57 result = [ left, right ];