work.suroh.tk/node_modules/lodash/startsWith.js

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2019-12-02 12:22:45 +00:00
var baseClamp = require('./_baseClamp'),
baseToString = require('./_baseToString'),
toInteger = require('./toInteger'),
toString = require('./toString');
/**
* Checks if `string` starts with the given target string.
*
* @static
* @memberOf _
* @since 3.0.0
* @category String
* @param {string} [string=''] The string to inspect.
* @param {string} [target] The string to search for.
* @param {number} [position=0] The position to search from.
* @returns {boolean} Returns `true` if `string` starts with `target`,
* else `false`.
* @example
*
* _.startsWith('abc', 'a');
* // => true
*
* _.startsWith('abc', 'b');
* // => false
*
* _.startsWith('abc', 'b', 1);
* // => true
*/
function startsWith(string, target, position) {
string = toString(string);
position = position == null
? 0
: baseClamp(toInteger(position), 0, string.length);
target = baseToString(target);
return string.slice(position, position + target.length) == target;
}
module.exports = startsWith;