37 lines
1.1 KiB
JavaScript
37 lines
1.1 KiB
JavaScript
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var baseToString = require('../internal/baseToString'),
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charsLeftIndex = require('../internal/charsLeftIndex'),
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isIterateeCall = require('../internal/isIterateeCall'),
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trimmedLeftIndex = require('../internal/trimmedLeftIndex');
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/**
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* Removes leading whitespace or specified characters from `string`.
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*
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* @static
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* @memberOf _
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* @category String
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* @param {string} [string=''] The string to trim.
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* @param {string} [chars=whitespace] The characters to trim.
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* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
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* @returns {string} Returns the trimmed string.
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* @example
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*
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* _.trimLeft(' abc ');
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* // => 'abc '
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*
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* _.trimLeft('-_-abc-_-', '_-');
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* // => 'abc-_-'
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*/
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function trimLeft(string, chars, guard) {
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var value = string;
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string = baseToString(string);
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if (!string) {
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return string;
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}
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if (guard ? isIterateeCall(value, chars, guard) : chars == null) {
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return string.slice(trimmedLeftIndex(string));
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}
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return string.slice(charsLeftIndex(string, (chars + '')));
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}
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module.exports = trimLeft;
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