While I personally miss the built in support of iterators. (I was working on a patch to Want.pm for Iterator context, but haven't had the time to finish), you can get the DWIM with iterator closures.
#!/usr/bin/perl
use warnings;
use strict;
sub char_iterator(\$){
my $str = shift;
my $count = 0;
return sub {
if (wantarray){
my ($tc,$len) = ($count, (length($$str) - $count) );
$count = length($$str);
return split('', substr($$str,$tc,$len));
}else{
return substr($$str,$count++,1);
}
}
}
my $string = join('', ('a'..'z') x 3);
my $chariter = char_iterator($string);
# Get one char at a time.
while(my $char = $chariter->() ){
print "Got $char\n";
}
# Get it in list context.
my $mapiter = char_iterator($string);
my @upper = map { uc($_)."\n" } $mapiter->();
print @upper;
update
I had a possible workaround to the "lazy evaluate" situation
here. I still plan to explore this further as time permits. I'd be interested to hear your thoughts.
-Lee
"To be civilized is to deny one's nature."
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