Beefy Boxes and Bandwidth Generously Provided by pair Networks
Pathologically Eclectic Rubbish Lister
 
PerlMonks  

Re: Challenge: Another Infinite Lazy List

by Limbic~Region (Chancellor)
on Mar 22, 2005 at 00:19 UTC ( #441347=note: print w/ replies, xml ) Need Help??


in reply to Challenge: Another Infinite Lazy List


My solution in the root thread required was only minimally better than my original solution (to the wrong problem). This minimally tested version is vast improvement over both previous solutions.

#!/usr/bin/perl use strict; use warnings; my $end = shift || 22; my $next = lazy_merge( [ @ARGV ? @ARGV : (2, 3, 5) ] ); print $next->(), "\n" for 1 .. $end; sub lazy_merge { my ($list, $last) = (shift(), 0); my $by_n = sub { my ($n, $k) = (shift(), 0); return sub { $_[0] ? +$k += $n : $k } }; $_ = $by_n->( $_ ) for @$list; return sub { my $low; for ( @$list ) { my $val = $_->(); $val = $_->( 'next' ) if $val <= $last; $low = $val if ! defined $low || $val < $low; } return $last = $low; }; }

Cheers - L~R


Comment on Re: Challenge: Another Infinite Lazy List
Download Code

Log In?
Username:
Password:

What's my password?
Create A New User
Node Status?
node history
Node Type: note [id://441347]
help
Chatterbox?
and the web crawler heard nothing...

How do I use this? | Other CB clients
Other Users?
Others having an uproarious good time at the Monastery: (12)
As of 2014-10-21 17:33 GMT
Sections?
Information?
Find Nodes?
Leftovers?
    Voting Booth?

    For retirement, I am banking on:










    Results (106 votes), past polls