This venerable variable demands more respect than many monks give it. Its might and glory are rarely actualized and this is a detriment to the perl community.

Observe this variables willingness to be noticed. 
$[++; # No go.
$[+=1; # Not happening
$[ = $[; # Works.
$[ = $[ + 1; # That will work!
print \$[; # Ok, works.
$[ = \$[; # which also works
print $[; # Whoo fun!

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Take notice to 'print \$[;' not to be confused with '$[ = \$[; print $[;', but the fun doesn't stop here monks!
$[=-1;
@_=qw/foo bar baz/;
print $_[-1]; # foo
print $_[-2]; # bar
print $_[-3]; # foo

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After playing with $[; I have taken note to this dire mistake that I apparently have made habit. And, now I have decided to publish a finding to enlighten all. This idiom is wrong, and must be corrected at all cost. 
#WRONG:
for(my $i=0; $i<$#foo; $i++){}
#RIGHT:
for(my $i=$[; $i<$#foo; $i++){}

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However, for the same reason this idiom is also wrong: 
#WRONG:
foreach(0..$#foo){}
#RIGHT:
foreach($[..$#foo){}

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Now that two bad commonplace practices have been exposed, I suggest that we enable warnings to be issued for people who use the 0..$#foo. These willy-nilly coding practices are detrimental should be discouraged. I see them much more severe than addressing an element with the array sigil, at least Perl can correct for that.

Evan Carroll
www.EvanCarroll.com

In reply to $[ is under respected. by EvanCarroll

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