See This node about the 'our' keyword for a discussion about the word "deprecated". Turns out that it really means "reserved" as in, it was used once, or may be used in the future.

At any rate, $# is fairly widely used, and $[ is not widely used, but I'd hardly call it one of the more obscure special variables. It's one that you should almost never change but it is perfectly alright to use. Not that I ever do, but: 

for $x ($] .. $#myarray)

## is actually technically better than 

for $x (0..$#myarray)

[download]
But still, the occasions to change it outside of an obfuscation are few and far between.

In reply to RE: Re: Should I use $[ and $# ? by turnstep
in thread Should I use $ and $# ? by Guildenstern

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