49 lines
1.3 KiB
JavaScript
49 lines
1.3 KiB
JavaScript
|
|
||
|
|
/**
|
||
|
|
* multiple ocurrences of:
|
||
|
|
* - alphabetical letter, underscore or dash, or
|
||
|
|
* - non-ascii character, or
|
||
|
|
* - escaped character
|
||
|
|
* @type {RegExp}
|
||
|
|
*/
|
||
|
|
var rIdentifier =
|
||
|
|
/(?:[A-Za-z0-9_-]|[^\0-\237]|\\(?:[^A-Fa-f0-9]|[A-Fa-f0-9]{1,6} ?))+/;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* backslash followed by a non-hexadecimal letter or
|
||
|
|
* a 1 to 6 digit hexadecimal number followed by an optional white space
|
||
|
|
* @type {RegExp}
|
||
|
|
*/
|
||
|
|
var rEscapedCharacter = /\\([^A-Fa-f0-9]|[A-Fa-f0-9]{1,6} ?)/g;
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Unescapes a single character
|
||
|
|
* @param {string} escapedCharacter escaped character starting with a backslash
|
||
|
|
* @return {string} unescaped character
|
||
|
|
*/
|
||
|
|
function unescapeCharacter(escapedCharacter) {
|
||
|
|
var escapeValue = escapedCharacter.substr(1);
|
||
|
|
var numberValue = parseInt(escapeValue, 16);
|
||
|
|
if (isNaN(numberValue)) {
|
||
|
|
return escapeValue;
|
||
|
|
}
|
||
|
|
|
||
|
|
return String.fromCharCode(numberValue);
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Unescapes all escaped characters in the given identifier
|
||
|
|
* @param {string} identifier identifier with possible escaped characters
|
||
|
|
* @return {string} unescaped identifier
|
||
|
|
*/
|
||
|
|
function unescapeIdentifier(identifier) {
|
||
|
|
return identifier.replace(rEscapedCharacter, unescapeCharacter);
|
||
|
|
}
|
||
|
|
|
||
|
|
module.exports = {
|
||
|
|
rIdentifier: rIdentifier,
|
||
|
|
rEscapedCharacter: rEscapedCharacter,
|
||
|
|
unescapeIdentifier: unescapeIdentifier,
|
||
|
|
unescapeCharacter: unescapeCharacter
|
||
|
|
};
|