undersc_rext.js

underscore extensions

version 0.0.2 (source)

a couple extemporaneous additions to everyone's fav_rite javascript library

ex•tem•po•ra•ne•ous |ikˌstempəˈrānēəs|
ajective

spoken or done without preparation: an extemporaneous speech.

 
             		           
                               
                            
                                
               
those are cobras, man
             		                            
/*globals exports:true,module*/
;(function() {
    var undersc_re = this._;
    if (typeof exports !== 'undefined') 
        undersc_re = exports = module.exports = require('underscore');

    undersc_re.mixin({
             		           
                               
                            
                                
               
_.memo(list, iterator, [memo], [context])



just like reduce except it automatically returns memo for you
each time.  and if you leave out the initial memo parameter, it
defaults to a new object.



params:



    

  • list: an array or object or something
    • 

  • iterator: a function that will be called as follows for each
item in list:
    


    iterator.call(context, memo, value, key)
    • 

  • memo (optional): return value of previous call to iterator.
defaults to an empty object literal {}
    • 

  • context: the context in which iterator will be called.
defaults to 'this'
    • 




returns: the return value from the last call of iterator
             		                            
        memo: function(list, iterator, memo, context) {
            memo = typeof memo === 'undefined'? {} : memo;
            context = typeof context === 'undefined'? memo : context;
            return undersc_re.reduce(list, function(memo) {
                iterator.apply(context, arguments);
                return memo;
            }, memo);
        },
             		           
                               
                            
                                
               
_.prop(obj, value, [key])



kinda like jquery prop() or attr().  in fact it's a lot like
jquery prop() and attr().  except for strait up js objects.



obj is updated w/ the properties using _.extend():



 _.extend(obj, props);




params:



    

  • obj: any js object
    • 

  • key: either a string for the property name or an object
    • 

  • value (optional): the value of the property (if a string was
given for key)
    • 




returns: the object.  what did you expect?
             		                            
        prop: function(obj, key, value) {
            var props = {};
            typeof value === 'undefined'? props = key : props[key] = value;
            return undersc_re.extend(obj, props);
        }
    });
}).apply(this);