Exception handling vs. hasNext()

Garrett Smith dhtmlkitchen at gmail.com
Fri Nov 16 17:30:01 PST 2007

Which is better?

var nodes : int;
var widgetMap = Widget.instances; // a map.
var it:Iterator<string> = widgetMap.getKeys();

 -- this: --

try {
catch(Exception e) {
  if(e instanceof StopIteration) {


 -- or this: --

while(it.hasNext()) {

It might be the case that there might be some error
I want to catch other than StopIteration. In that case, to be
backwards-compatible and work across implementations, the developer
must use conditional
checks inside 1 catch block.

A hasNext() would not prevent the developer from writing such code.
Omitting hasNext() forces developers to use exception handling for
non-exceptional condition.

How does using try/catch for normal termination of the loop look?

It looks like all exceptions are unchecked in ES4. correct?  (I cannot
verify this to be true because
I am unable to access the spec namespace on ecmascript.org.)

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