blob: 30f4f47a2df2c15bf921438a7d19cf055736857b [file] [log] [blame]
var baseToString = require('./_baseToString'),
castSlice = require('./_castSlice'),
charsStartIndex = require('./_charsStartIndex'),
stringToArray = require('./_stringToArray'),
toString = require('./toString');
/** Used to match leading and trailing whitespace. */
var reTrimStart = /^\s+/;
/**
* Removes leading whitespace or specified characters from `string`.
*
* @static
* @memberOf _
* @since 4.0.0
* @category String
* @param {string} [string=''] The string to trim.
* @param {string} [chars=whitespace] The characters to trim.
* @param- {Object} [guard] Enables use as an iteratee for methods like `_.map`.
* @returns {string} Returns the trimmed string.
* @example
*
* _.trimStart(' abc ');
* // => 'abc '
*
* _.trimStart('-_-abc-_-', '_-');
* // => 'abc-_-'
*/
function trimStart(string, chars, guard) {
string = toString(string);
if (string && (guard || chars === undefined)) {
return string.replace(reTrimStart, '');
}
if (!string || !(chars = baseToString(chars))) {
return string;
}
var strSymbols = stringToArray(string),
start = charsStartIndex(strSymbols, stringToArray(chars));
return castSlice(strSymbols, start).join('');
}
module.exports = trimStart;