Created
January 12, 2012 19:04
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key selection, remapping
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| var selectKeys = function(hash, keys) { | |
| var output, prop, index; | |
| output = {}; | |
| if(!keys) return {}; | |
| if(keys instanceof Array) { | |
| for(index = 0; index < keys.length; index++) { | |
| output[keys[index]] = hash[keys[index]]; | |
| } | |
| return output; | |
| } | |
| for(prop in keys) { | |
| if(keys.hasOwnProperty(prop)) { | |
| if(typeof keys[prop] === 'boolean') { | |
| if(keys[prop]) output[prop] = hash[prop]; | |
| // if false, don't copy the property | |
| } else { | |
| output[keys[prop]] = hash[prop]; | |
| } | |
| } | |
| } | |
| return output; | |
| }; |
Author
Yep. Good point. Renaming it to selectKeys, made it select (and not remap) keys if given an array, and if given an object can remap them.
Line 4 you can use if (!keys) instead of checking for undefined. That will catch null too.
Author
Nice. Changed it. That's a win for compression, too, since typestrings can't be compressed but variable names can.
Line 1 has a syntax error. You can drop the selectKeys:.
var selectKeys = selectKeys: function(hash, keys) {
Author
That's what I get for copying+pasting out of an object literal.
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Oh I see, it's renaming the keys. Maybe this function would be better named "rename-keys"? I got thrown by the use of "parse" and "options"; "parse options" sounds to me like parsing command-line flags.