error handling - Catching "NullPointerExceptions" in JavaScript -

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i'm writing quite bit of code in prototype.js returns null if dom-id wasn't found.

$("someid").show();

if someid doesn't exist, method called on null, halts entire program, in effect disabling js effects after error. check null before executing such statement, getting tiring.

i catch exception i'm not sure 1 is. mdc lists following ecma script error types, on first glance none of them seem want:

* error * evalerror * rangeerror * referenceerror * syntaxerror * typeerror * urierror * domexception * eventexception * rangeexception

also, browsers have unified way of dealing method call on null?

i don't believe there's unity found. chrome throws typeerror, ie throws error, have catch , make severe assumptions. better check null first.

var element = $('someid'); if (element) {     element.show();     // whatever else... }

if element.show() thing need for, can written lot shorter, in cases appropriate.


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