jquery-ui/release/build/js/ParseMaster.js
2008-06-07 20:02:49 +00:00

107 lines
4.4 KiB
JavaScript

/*
ParseMaster, version 1.0.2 (2005-08-19)
Copyright 2005, Dean Edwards
License: http://creativecommons.org/licenses/LGPL/2.1/
*/
/* a multi-pattern parser */
// KNOWN BUG: erroneous behavior when using escapeChar with a replacement value that is a function
function ParseMaster() {
// constants
var $EXPRESSION = 0, $REPLACEMENT = 1, $LENGTH = 2;
// used to determine nesting levels
var $GROUPS = /\(/g, $SUB_REPLACE = /\$\d/, $INDEXED = /^\$\d+$/,
$TRIM = /(['"])\1\+(.*)\+\1\1$/, $$ESCAPE = /\\./g, $QUOTE = /'/,
$$DELETED = /\x01[^\x01]*\x01/g;
var self = this;
// public
this.add = function($expression, $replacement) {
if (!$replacement) $replacement = "";
// count the number of sub-expressions
// - add one because each pattern is itself a sub-expression
var $length = (_internalEscape(String($expression)).match($GROUPS) || "").length + 1;
// does the pattern deal with sub-expressions?
if ($SUB_REPLACE.test($replacement)) {
// a simple lookup? (e.g. "$2")
if ($INDEXED.test($replacement)) {
// store the index (used for fast retrieval of matched strings)
$replacement = parseInt($replacement.slice(1)) - 1;
} else { // a complicated lookup (e.g. "Hello $2 $1")
// build a function to do the lookup
var i = $length;
var $quote = $QUOTE.test(_internalEscape($replacement)) ? '"' : "'";
while (i) $replacement = $replacement.split("$" + i--).join($quote + "+a[o+" + i + "]+" + $quote);
$replacement = new Function("a,o", "return" + $quote + $replacement.replace($TRIM, "$1") + $quote);
}
}
// pass the modified arguments
_add($expression || "/^$/", $replacement, $length);
};
// execute the global replacement
this.exec = function($string) {
_escaped.length = 0;
return _unescape(_escape($string, this.escapeChar).replace(
new RegExp(_patterns, this.ignoreCase ? "gi" : "g"), _replacement), this.escapeChar).replace($$DELETED, "");
};
// clear the patterns collection so that this object may be re-used
this.reset = function() {
_patterns.length = 0;
};
// private
var _escaped = []; // escaped characters
var _patterns = []; // patterns stored by index
var _toString = function(){return "(" + String(this[$EXPRESSION]).slice(1, -1) + ")"};
_patterns.toString = function(){return this.join("|")};
// create and add a new pattern to the patterns collection
function _add() {
arguments.toString = _toString;
// store the pattern - as an arguments object (i think this is quicker..?)
_patterns[_patterns.length] = arguments;
}
// this is the global replace function (it's quite complicated)
function _replacement() {
if (!arguments[0]) return "";
var i = 1, j = 0, $pattern;
// loop through the patterns
while ($pattern = _patterns[j++]) {
// do we have a result?
if (arguments[i]) {
var $replacement = $pattern[$REPLACEMENT];
switch (typeof $replacement) {
case "function": return $replacement(arguments, i);
case "number": return arguments[$replacement + i];
}
var $delete = (arguments[i].indexOf(self.escapeChar) == -1) ? "" :
"\x01" + arguments[i] + "\x01";
return $delete + $replacement;
// skip over references to sub-expressions
} else i += $pattern[$LENGTH];
}
};
// encode escaped characters
function _escape($string, $escapeChar) {
return $escapeChar ? $string.replace(new RegExp("\\" + $escapeChar + "(.)", "g"), function($match, $char) {
_escaped[_escaped.length] = $char;
return $escapeChar;
}) : $string;
};
// decode escaped characters
function _unescape($string, $escapeChar) {
var i = 0;
return $escapeChar ? $string.replace(new RegExp("\\" + $escapeChar, "g"), function() {
return $escapeChar + (_escaped[i++] || "");
}) : $string;
};
function _internalEscape($string) {
return $string.replace($$ESCAPE, "");
};
};
ParseMaster.prototype = {
constructor: ParseMaster,
ignoreCase: false,
escapeChar: ""
};