RonW,

I also have a C background, and agree about "state" variables being the Perl equivalent of C "static" variables.

Using "state" simplifies cases like the following where one shouldn't have to remember to print an HTML header, but also doesn't want it more than once: 

#!/usr/bin/perl

use strict;
use warnings;
use feature qw{ state };

sub html {
    my ($text) = @_;

    # Make the header idempotent
    state $b_header++ or print "Content-type: text/html\n\n";

    print $text;
}

html("<br>This is some html, prior to which a header is printed\n");
html("<br>This is too (but the header was printed already)\n");

[download]

Output: 

Content-type: text/html

<br>This is some html, prior to which a header is printed
<br>This is too (but the header was printed already)

[download]
say  substr+lc crypt(qw $i3 SI$),4,5

In reply to Re^9: Experimental features: autoderef vs postfix deref by golux
in thread Experimental features: autoderef vs postfix deref by stevieb

Title:
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