function baseToNumber(value) {
      if (typeof value == 'number') {
        return value;
      }
      if (isSymbol(value)) {
        return NAN;
      }
      return +value;
    }
The base implementation of `_.toNumber` which doesn't ensure correct
conversions of binary, hexadecimal, or octal string values.

@private
@param {*} value The value to process.
@returns {number} Returns the number.