Do you know where your variables are? PerlMonks

### Comment on

 Need Help??
Old discussion, but I figure I'll throw in my attempt at calculating primes without modules, and using only recursive functions (no loops)
```#!/usr/bin/env perl

use strict;
use warnings;
use 5.010;

\$DB::deep = 500;
\$DB::deep = \$DB::deep; # Avoids silly 'used only once' warning

no warnings "recursion";

# Identify primes between ARG0 and ARG1

my (\$x, \$y, \$re_int, \$result);
my (\$prime, \$is_int);

\$x = \$ARGV[0];
\$y = \$ARGV[1];

\$is_int = sub {
my \$re_int = qr(^-?\d+\z);
my (\$x) = @_;
\$x =~ \$re_int
? 1
: 0;
};

\$prime = sub {
my ( \$x, \$y ) = @_;
if ( \$y > 1 ) {
given (\$x) {
when ( \$is_int->( \$x / \$y ) ) {
return 0;
}
default {
return \$prime->( \$x, \$y - 1 );
}
}
}
else { return 1; }
};

\$result = sub {
my ( \$x, \$y ) = @_;
if ( \$x <= \$y ) {
if ( \$prime->(\$x, \$x-1) ) {
say \$x;
}
\$result->( ( \$x + 1 ), \$y );
}
};

\$result->(\$x, \$y);
Originally posted the above to my blog.

In reply to Re: Prime Number Finder by jbl_bomin
in thread Prime Number Finder by munchie

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post; it's "PerlMonks-approved HTML":

• Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
• Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
• Read Where should I post X? if you're not absolutely sure you're posting in the right place.
• Posts may use any of the Perl Monks Approved HTML tags:
a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
• You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
 For: Use: & & < < > > [ [ ] ]
• Link using PerlMonks shortcuts! What shortcuts can I use for linking?

Create A New User
Chatterbox?
 [GotToBTru]: it's always teatime somewhere erix the sun never sets on the CB

How do I use this? | Other CB clients
Other Users?
Others scrutinizing the Monastery: (11)
As of 2017-04-24 12:29 GMT
Sections?
Information?
Find Nodes?
Leftovers?
Voting Booth?
I'm a fool:

Results (439 votes). Check out past polls.