Running count in map

Solo has asked for the wisdom of the Perl Monks concerning the following question:

Is there a special variable that holds the index to the current element for a map? Or any other way besides a global variable to keep a running count in a map? I'm hoping something exists for map like @- for regexps, but I can't find it if it does.

--Solo --
You said you wanted to be around when I made a mistake; well, this could be it, sweetheart.

Comment on Running count in map

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Re: Running count in map by diotalevi (Canon) on Aug 06, 2004 at 18:09 UTC
dragonchild has it though you'll have to ignore the confusing way he said it. You don't need a global, just a variable that is accessible. my()'d variables are perfectly acceptable here. `my $counter = 0; ... map { ++$counter; ... } ...` [download]	[reply] [d/l]
Re: Running count in map by Prior Nacre V (Hermit) on Aug 06, 2004 at 18:11 UTC
You can do something like: `my @map_list = ( ... ); map { process $map_list[$_] } (0 .. $#map_list)` [download] Regards, PN5	[reply] [d/l]
Re: Running count in map by dragonchild (Archbishop) on Aug 06, 2004 at 18:04 UTC
map doesn't maintain state, just like grep doesn't. They operate on lists, not items in the list. ------ We are the carpenters and bricklayers of the Information Age. Then there are Damian modules.... sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon.* - flyingmoose I shouldn't have to say this, but any code, unless otherwise stated, is untested	[reply]
Re^2: Running count in map by Fletch (Bishop) on Aug 06, 2004 at 18:35 UTC
Of course `$_` is an alias for the original items in the list so you can use it to modify the original items if you want.</pedant> (not that that answers the original is-there-an-index question)	[reply] [d/l]