marcoonroad

\ == recursive version ==

: fib
  dup 2 <= if
    drop 1
  else
    dup 1 - recurse
    swap 2 - recurse +
  then ;

marcoonroad

#!/home/user/localperl/bin/perl

use v5.20;
use strict;
use warnings;
use feature qw| say signatures |;

my %multi;

sub def ($name, $param, $lambda) {

marcoonroad

#!/usr/bin/perl6

use v6;

# overloading string 'x' operator
multi infix:<x> (Int \a, Int \b) { a * b }

# but we still want the string 'x' operator
multi infix:<x> (Str \a, Int \b where * > 1) { [~] gather for ^b { take a } }

marcoonroad

-- defac as multi-dispatch pseudo-code
--
-- defac(x):    defac(x / 1, 1)     [ where x is Integer ]
-- defac(x, d): d - x               [ where x = 1 ]
-- defac(x, d): error()             [ where x < 1 ]
-- defac(x, d): defac(x / d, d + 1) [ where x > 1 ]

function defac (x, d)
  d = d or 1
  if x == 1 then

marcoonroad

-- as multi-dispatch pseudo-code
--
-- range(init, final, step):
---- return
---- [ where init > final ]
--
-- range(final):
---- return 0, range(0 + 1, final, 1)
---- [ where final is Positive Integer ]
--

marcoonroad

#!/usr/bin/perl6

use v6;

multi fib(Int $n where -> $n { $n ~~ any(1, 2) }) { 1 }
multi fib(Int $n where -> $n { $n > 2 }) { fib($n - 1) + fib($n - 2) }

say fib 10; # 55

marcoonroad

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

// max & min size of strings
#define MIN   50
#define MAX  500
// limit of messages
#define MSGS 100

marcoonroad

# ~~~            | n + 1                 :@: if m = 0            ~~~ #
# ~~~  A(m, n) = | A(m - 1, 1)           :@: if m > 0 and n = 0  ~~~ #
# ~~~            | A(m - 1, A(m, n - 1)  :@: if m > 0 and n > 0  ~~~ #

multi A($m where(* == 0), $n              ) { $n + 1 }
multi A($m where(*  > 0), $n where(* == 0)) { A($m - 1, 1) }
multi A($m where(*  > 0), $n where(*  > 0)) { A($m - 1, A($m, $n - 1)) }

say A(1, 2);

marcoonroad

#!/usr/bin/perl6

use v6;

multi chain ([ ]) { [ head => [ ] ] }
multi chain (@Ls) { [ head => @Ls.shift, tail => chain @Ls ] }

# test
my @chained = chain [ 1, 2, 3 ];
say @chained.perl;

marcoonroad

-- if and else as methods (test) --

-- object --
local logic = { main = nil }

-- if method --
function logic: so(code)
	if self.main then
		code( )
	end