How do you know which parameters to set for a javascript function? -
coming java, javascript can frustrating. i'm hoping can put simple terms me. i'm struggling understand how javascript programmers know parameters pass method they're calling - when method being called callback (which in eyes seems added level of complexity). for example , take function addeventlistener . in function, typical use looks like mydomitem.addeventlistener("click", function(e){...}, false); in documentation function (hyperlinked name above) don't see mention of option. whereas in java can know if parameters match type ide, in javascript seems huge guessing game or requires serious in-depth knowledge of each function. how javascript programmers it? the documentation linked show form in example: target.addeventlistener(type, listener[, usecapture]); the type parameter string "click" , listener function object, , usecapture false .