Does jQuery do any kind of caching of “selectors”?

Question

For example, will the first piece of code perform a full search twice, or is it smart enough to cache results if no DOM changes have occurred?

if ($(\"#navba         


        

Answer 1

Similar to your $$ approach, I created a function (of the same name) that uses a memorization pattern to keep global cleaner and also accounts for a second context parameter... like $$(".class", "#context"). This is needed if you use the chained function find() that happens after $$ is returned; thus it will not be cached alone unless you cache the context object first. I also added boolean parameter to the end (2nd or 3rd parameter depending on if you use context) to force it to go back to the DOM.

Code:

function $$(a, b, c){
    var key;
    if(c){
        key = a + "," + b;
        if(!this.hasOwnProperty(key) || c){
            this[key] = $(a, b);
        }        
    }
    else if(b){
        if(typeof b == "boolean"){  
            key = a;  
            if(!this.hasOwnProperty(key) || b){
                this[key] = $(a);
            }
        }
        else{
            key = a + "," + b;
            this[key] = $(a, b);   
        }            
    }
    else{
        key = a;
        if(!this.hasOwnProperty(key)){
            this[key] = $(a);
        } 
    }
    return this[key]; 
}

Usage:

a

    
b
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