lib/lodash.js
function toInteger(value) {
      if (!value) {
        return value === 0 ? value : 0;
      }
      value = toNumber(value);
      if (value === INFINITY || value === -INFINITY) {
        var sign = (value < 0 ? -1 : 1);
        return sign * MAX_INTEGER;
      }
      var remainder = value % 1;
      return value === value ? (remainder ? value - remainder : value) : 0;
    }
function toInteger(value) {
      if (!value) {
        return value === 0 ? value : 0;
      }
      value = toNumber(value);
      if (value === INFINITY || value === -INFINITY) {
        var sign = (value < 0 ? -1 : 1);
        return sign * MAX_INTEGER;
      }
      var remainder = value % 1;
      return value === value ? (remainder ? value - remainder : value) : 0;
    }
Converts `value` to an integer.

**Note:** This function is loosely based on [`ToInteger`](http://www.ecma-international.org/ecma-262/6.0/#sec-tointeger).

@static
@memberOf _
@category Lang
@param {*} value The value to convert.
@returns {number} Returns the converted integer.
@example

_.toInteger(3);
// => 3

_.toInteger(Number.MIN_VALUE);
// => 0

_.toInteger(Infinity);
// => 1.7976931348623157e+308

_.toInteger('3');
// => 3