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### Re: Re: Re: Perl 6 is too complex

by broquaint (Abbot)
 on Mar 17, 2003 at 11:55 UTC ( #243621=note: print w/replies, xml ) Need Help??

in reply to Re: Re: Perl 6 is too complex
in thread Perl 6 is too complex

Also to be an even closer conversion would require apply to tie @squares to a square generator
Ok, perhaps not a square generator, but maybe something like this
```use strict;

{
package Tie::Array::Apply;

'@{}'    => sub { \$_[0]->{list} },
fallback => 1;

use Tie::Array;

@Tie::Array::Apply::ISA = qw( Tie::StdArray );

sub TIEARRAY {
my \$class = shift;

bless { func => shift, list => [@_], array => []}, \$class;
}

sub FETCH {
my(\$self,\$pos) = @_;

return \$self->{array}->[\$pos]
if exists \$self->{array}->[\$pos];

return undef
if \$pos >= @{ \$self->{list} };

local \$_ = \$self->{list}->[\$pos];
return \$self->{array}->[\$pos] = \$self->{func}->();
}
}

sub bind_apply(&@) {
tie my @ret, 'Tie::Array::Apply', @_;
return @ret;
}

my @bind_squares = bind_apply { \$_ * \$_ } 2 .. 5;

print "bind_apply: ", join(', ', @bind_squares), \$/;

__output__

bind_apply: 4, 9, 16, 25
That code will lazily evaluate a list where each indice is bound to a function which has the appropriate element in the initial list applied to it. But now it doesn't have the recursive behaviour demonstrated in the original perl6 function so no longer needs a funky prototype or multimethod dispatch. Ho hum.
HTH

_________
broquaint

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