index.umd.js
function callIf(condition, func) {
    return (
      condition
        ? func.apply(undefined, Array.prototype.slice.call(arguments, 2))
        : undefined
    );
  }
function callIf(condition, func) {
    return (
      condition
        ? func.apply(undefined, Array.prototype.slice.call(arguments, 2))
        : undefined
    );
  }
@param  {Boolean}  condition - Condition used to determine whether to call end
return the result of `func` or `undefined`.
@param  {Function} func      - Function to be called if `condition` evaluates to
`true`.
@param  {...?*}    funcParams - Parameters to be passed to `func`, if called.

@returns {?*} Result of calling `func` if given `condition` evaluates to `true`;
otherwise, returns `undefined`.