blob: f457711e49d382a5ceb303aaf37b38a3617a8a1f [file] [log] [blame]
var isIterateeCall = require('../internal/isIterateeCall'),
trim = require('./trim');
/** Used to detect hexadecimal string values. */
var reHasHexPrefix = /^0[xX]/;
/* Native method references for those with the same name as other `lodash` methods. */
var nativeParseInt = global.parseInt;
/**
* Converts `string` to an integer of the specified radix. If `radix` is
* `undefined` or `0`, a `radix` of `10` is used unless `value` is a hexadecimal,
* in which case a `radix` of `16` is used.
*
* **Note:** This method aligns with the [ES5 implementation](https://es5.github.io/#E)
* of `parseInt`.
*
* @static
* @memberOf _
* @category String
* @param {string} string The string to convert.
* @param {number} [radix] The radix to interpret `value` by.
* @param- {Object} [guard] Enables use as a callback for functions like `_.map`.
* @returns {number} Returns the converted integer.
* @example
*
* _.parseInt('08');
* // => 8
*
* _.map(['6', '08', '10'], _.parseInt);
* // => [6, 8, 10]
*/
function parseInt(string, radix, guard) {
// Firefox < 21 and Opera < 15 follow ES3 for `parseInt`.
// Chrome fails to trim leading <BOM> whitespace characters.
// See https://code.google.com/p/v8/issues/detail?id=3109 for more details.
if (guard ? isIterateeCall(string, radix, guard) : radix == null) {
radix = 0;
} else if (radix) {
radix = +radix;
}
string = trim(string);
return nativeParseInt(string, radix || (reHasHexPrefix.test(string) ? 16 : 10));
}
module.exports = parseInt;