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

Comment on

( #3333=superdoc: print w/ replies, xml ) Need Help??

I am confused. Where is the "infinite lazy list"?

In the implementation I posted, a variable like

my $lazy235 = challenge( 2, 3, 5 );
is, effectively, an infinite lazy list. One can repeatedly extract an arbitrarily long prefix from it, using take, or repeatedly find its n-th element with something like:
sub nth { my $ll = shift; my $n = shift; die "Invalid argument: $n\n" if $n < 0; return $n == 0 ? head( $ll ) : nth( tail( $ll ), $n - 1 ); }
For example, the following:
my @first_50 = take( 50, $lazy235 ); my @again = take( 50, $lazy235 ); print "@first_50\n\n@again\n\n"; for ( map int( rand( 1000 ) ), ( 1 .. 5 ) ) { printf "%3d %d\n", $_, nth( $lazy235, $_ ); }
prints out something like
0 2 3 4 5 6 8 9 10 12 14 15 16 18 20 21 22 24 25 26 27 28 30 32 33 34 +35 36 38 39 40 42 44 45 46 48 50 51 52 54 55 56 57 58 60 62 63 64 65 +66 0 2 3 4 5 6 8 9 10 12 14 15 16 18 20 21 22 24 25 26 27 28 30 32 33 34 +35 36 38 39 40 42 44 45 46 48 50 51 52 54 55 56 57 58 60 62 63 64 65 +66 347 474 857 1168 530 723 994 1355 579 789

the lowliest monk


In reply to Re^3: Challenge: Another Infinite Lazy List by tlm
in thread Challenge: Another Infinite Lazy List by Limbic~Region

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!
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • 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
  • Outside of code tags, you may need to use entities for some characters:
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.
  • Log In?
    Username:
    Password:

    What's my password?
    Create A New User
    Chatterbox?
    and the web crawler heard nothing...

    How do I use this? | Other CB clients
    Other Users?
    Others taking refuge in the Monastery: (7)
    As of 2014-11-01 00:38 GMT
    Sections?
    Information?
    Find Nodes?
    Leftovers?
      Voting Booth?

      For retirement, I am banking on:










      Results (227 votes), past polls