Beefy Boxes and Bandwidth Generously Provided by pair Networks
There's more than one way to do things

Re^4: how to pull in all params that are numbered

by imp (Priest)
on Jun 18, 2007 at 18:46 UTC ( #621855=note: print w/replies, xml ) Need Help??

in reply to Re^3: how to pull in all params that are numbered
in thread how to pull in all params that are numbered

The problem is that while does not iterate over a list, it simply checks for a true value. For example, while (1){} will run forever, whereas for (1){} will run once.

The same behaviour occurs when test being evaluated is param(). Additionally, while (param()){} will not modify $_. Perhaps you tested the script without any arguments, in which case it would have behaved as expected.

Here is a simple test:

#!/usr/bin/perl use strict; use warnings; use CGI qw(param); my $runs =0; my @num; print "Content-type: text/plain\n\n"; while(param()) { printf "run %d\n", $runs++; if ($runs > 10) { print "Ran over 10 times\n"; exit; } }
You can verify it by adding the parameters on the commandline, e.g.
perl a=b

Log In?

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://621855]
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others drinking their drinks and smoking their pipes about the Monastery: (10)
As of 2016-10-26 09:54 GMT
Find Nodes?
    Voting Booth?
    How many different varieties (color, size, etc) of socks do you have in your sock drawer?

    Results (338 votes). Check out past polls.