FOP utilities, Perl

FOP utilities

#perl 5.26.1 
#some utilities function to bring some more FOP flavour.

sub foldl{my $f=shift; my $r=shift;
    $r=&$f($r,shift) while scalar(@_); $r}
sub foldr{my $f=shift; my $r=shift;
    $r=&$f(pop,$r) while scalar(@_); $r}

sub curry{my $f=shift;
    sub{return &$f unless scalar(@_);
        my @a=@_; curry(sub {$f->(@a,@_)})}}
sub uncurry{my $f=shift; sub{$f->(@_)()}}
#e.g. $f=sub{foldl sub{$_[0]+$_[1]}, 0,@_};
#     curry($f)->(1)(2)(3,4,5)(6)() == $f->(1,2,3,4,5,6) ==21
sub curry_once{my $f=shift;
    sub{my @a=@_; sub{$f->(@a,@_)}}}
sub comp{my $f=shift; (ref $f eq 'CODE')?&$f:$f}

sub zipWith($++){my $f=shift;
    my @a=@{;shift}; my @b=@{;shift};
    map {$f->($a[$_],$b[$_])} (0.._min($#a,$#b))}

sub zip(++){unshift @_,sub{[@_]}; goto &zipWith}

sub zipWithMany{my $f=shift;
    $f=(ref $f eq 'ARRAY')?$$f[0]:curry($f);        # MAGIC.
    if(scalar(@_)==1){return map {$_->()} @{$_[0]}} # TILTOWAIT!
    my @a=zipWith($f,shift,shift);
    my $ap=sub{$_[0]->($_[1])};
    zipWithMany([$ap],[@a],@_)}

sub rec{my $f=curry_once shift;        #the Y combinator, folks!
    sub{my $x=shift; $x->($x)}->(      #using it is a BAD idea!
        sub{my $y=shift; $f->(         
            sub{$y->($y)->(@_)})})}

sub Op{my $op=shift; sub{eval"\$_[0]$op\$_[1]"}}
#e.g. (Op '+') is the addition function

sub _min{$_[0]<$_[1]?$_[0]:$_[1]}


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