Hi all, I'm fairly new to Perl, and lately I've been converting my old awk scripts to Perl by using a2p. I'm running version 5.004_04 on Irix. (I know there's a newer version but our admins are tied down by corporate red tape when it comes to installing software). Anyway, I noticed that it always inserts these three lines in the generated Perl code: 
$[ = 1;    # set array base to 1
$, = ' ';    # set output field separator
$\ = "\n";    # set output record separator

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I'm puzzled by the $[ variable. I read in Programming Perl that it's set to 1:
"...to make Perl behave more like awk...when evaluating the index and substr functions".
I don't mind using 0 as the array base so I started tinkering around with this variable just to see what would happen. Well, nothing happened when I changed it. Shouldn't it have some effect on arrays like this?: 
...
while (<FILE>) {
     chomp;    # strip record separator
     @in_data = split(/ +/, $_);
     ...

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I changed the array base to 0, 1, 5, 20, etc. and it had no effect on my program. So I read further in Programming Perl, (the next line as a matter of fact =), and it says:
"Because it was found to be so dangerous, assignment to $[ is now treated as a lexically scoped compiler directive and cannot influence the behavior of any other file."
Well I have no clue what that means. I was wondering if any of you could shed some light on what this variable does. I tried Super Search, but it keeps giving me errors. Thanks!

In reply to Special variable - set array base by licking9Volts

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