lib/util.js
function(callback) {
                var ret,
                    isFunc  = Util.type.function(callback),
                    args    = [].slice.call(arguments, 1);
               
                if (isFunc)
                    ret     = callback.apply(null, args);
                
                return ret;
            }
function(callback) {
                var ret,
                    isFunc  = Util.type.function(callback),
                    args    = [].slice.call(arguments, 1);
               
                if (isFunc)
                    ret     = callback.apply(null, args);
                
                return ret;
            }
function ( callback ) { var ret , isFunc = Util . type . function ( callback ) , args = [ ] . slice . call ( arguments , 1 ) ; if ( isFunc ) ret = callback . apply ( null , args ) ; return ret ; }
function do save exec of function
@param callback
@param arg1
...
@param argN
function do save exec of function