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/**
@name String
@class Additions to the core string object.
*/
/** @author Steven Levithan, released as public domain. */
String.prototype.trim = function() {
var str = this.replace(/^\s+/, '');
for (var i = str.length - 1; i >= 0; i--) {
if (/\S/.test(str.charAt(i))) {
str = str.substring(0, i + 1);
break;
}
}
return str;
}
/*t:
plan(6, "Testing String.prototype.trim.");
var s = " a bc ".trim();
is(s, "a bc", "multiple spaces front and back are trimmed.");
s = "a bc\n\n".trim();
is(s, "a bc", "newlines only in back are trimmed.");
s = "\ta bc".trim();
is(s, "a bc", "tabs only in front are trimmed.");
s = "\n \t".trim();
is(s, "", "an all-space string is trimmed to empty.");
s = "a b\nc".trim();
is(s, "a b\nc", "a string with no spaces in front or back is trimmed to itself.");
s = "".trim();
is(s, "", "an empty string is trimmed to empty.");
*/
String.prototype.balance = function(open, close) {
var i = 0;
while (this.charAt(i) != open) {
if (i == this.length) return [-1, -1];
i++;
}
var j = i+1;
var balance = 1;
while (j < this.length) {
if (this.charAt(j) == open) balance++;
if (this.charAt(j) == close) balance--;
if (balance == 0) break;
j++;
if (j == this.length) return [-1, -1];
}
return [i, j];
}
/*t:
plan(16, "Testing String.prototype.balance.");
var s = "{abc}".balance("{","}");
is(s[0], 0, "opener in first is found.");
is(s[1], 4, "closer in last is found.");
s = "ab{c}de".balance("{","}");
is(s[0], 2, "opener in middle is found.");
is(s[1], 4, "closer in middle is found.");
s = "a{b{c}de}f".balance("{","}");
is(s[0], 1, "nested opener is found.");
is(s[1], 8, "nested closer is found.");
s = "{}".balance("{","}");
is(s[0], 0, "opener with no content is found.");
is(s[1], 1, "closer with no content is found.");
s = "".balance("{","}");
is(s[0], -1, "empty string opener is -1.");
is(s[1], -1, "empty string closer is -1.");
s = "{abc".balance("{","}");
is(s[0], -1, "opener with no closer returns -1.");
is(s[1], -1, "no closer returns -1.");
s = "abc".balance("{","}");
is(s[0], -1, "no opener or closer returns -1 for opener.");
is(s[1], -1, "no opener or closer returns -1 for closer.");
s = "a<bc}de".balance("<","}");
is(s[0], 1, "unmatching opener is found.");
is(s[1], 4, "unmatching closer is found.");
*/
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