Where Are The Wise Men?

As I was working on some JavaScript code this week, I stopped and thought awhile about how I could get around putting a C-style ;for statement. You know what I mean — I was trying to get away from this:

for (i=0; i

item = list[i];
// do stuff
}

And then I realized something that has always been subtle yet very true to me — I hate the C-style for statement and I avoid it whenever and wherever possible. I think this came about when I started in Python — it’s for statement is very different than the one above. The analogous in Python would be:

for (thing in list):
# do stuff

It’s more like an iterator than a traditional for-statement, because you can only have a for statement on a sequence. What to just have the number 1 through 10? Then put them in a sequence with the range function:

for (num in range(1,10)):
// do stuff

In Java you can do the C-style if you want to, but I tend to avoid them altogether and use iterators pretty much exclusively:

Iterator it = list.iterator();

while(it.hasNext()) {
Object obj = it.next();
//do stuff
}

JavaScript 1.6 has a forEach closure in it’s Array object, but IE only supports JavaScript 1.5. So I usually do the following:

for (var idx in list) {
var obj=list[idx];
// do stuff
}

Similar to the Python version, but you get the index the Array, not the value. An interesting quirk by a nice one if you have an associative array.

So why don’t I like the traditional, tried-and-true for style? Because I think it’s prone to breakage and delicate. It’s also really a three-statement command: set the value, tell the test command, and increment, in once step. and I tend to typo something in there like:

• Misplace a semicolon
• Use <= instead of just <
• Forget a + at the end of the increment
• Forget a bracket at the end

The less complicate the code, the better off we all our.

This entry was posted on Tuesday, May 1st, 2007 at 11:24 am and is filed under Life. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.