=head1 VERSION
-Version 0.04
+Version 0.08
=cut
use vars qw/$VERSION/;
-$VERSION = '0.04';
+$VERSION = '0.08';
=head1 SYNOPSIS
- use Sub::Prototype::Util qw/flatten recall/;
+ use Sub::Prototype::Util qw/flatten recall wrap/;
my @a = qw/a b c/;
my @args = ( \@a, 1, { d => 2 }, undef, 3 );
my @flat = flatten '\@$;$', @args; # ('a', 'b', 'c', 1, { d => 2 })
recall 'CORE::push', @args; # @a contains 'a', 'b', 'c', 1, { d => 2 }, undef, 3
+ my $splice = wrap 'CORE::splice', compile => 1;
+ my @b = $splice->(\@a, 4, 2); # @a is now ('a', 'b', 'c', 1, 3) and @b is ({ d => 2 }, undef)
=head1 DESCRIPTION
=cut
my %sigils = qw/SCALAR $ ARRAY @ HASH % GLOB * CODE &/;
+my %reftypes = reverse %sigils;
sub _check_ref {
my ($a, $p) = @_;
will call C<push @$a, 1, 2, 3> and so fill the arrayref C<$a> with C<1, 2, 3>. This is especially needed for core functions because you can't C<goto> into them.
+You can also force the use of a specific prototype. In this case, C<$name> must be a hash reference that holds exactly one key/value pair, the key being the function name and the value the prototpye that should be used to call it.
+
+ recall { 'CORE::push' => '\@$' }, $a, 1, 2, 3; # will only push 1
+
+This allows you to recall into C<CORE::grep> and C<CORE::map> by using the C<\&@> prototype :
+
+ sub mygrep (&@) { recall { 'CORE::grep' => '\&@' }, @_ } # the prototypes are intentionally different
+
=cut
-sub recall {
- my $name = shift;
- croak 'Wrong subroutine name' unless $name;
+sub _check_name {
+ my $name = $_[0];
+ croak 'No subroutine specified' unless $name;
+ my $proto;
+ my $r = ref $name;
+ if (!$r) {
+ $proto = prototype $name;
+ } elsif ($r eq 'HASH') {
+ croak 'Forced prototype hash reference must contain exactly one key/value pair' unless keys %$name == 1;
+ ($name, $proto) = %$name;
+ } else {
+ croak 'Unhandled ' . $r . ' reference as first argument';
+ }
$name =~ s/^\s+//;
$name =~ s/[\s\$\@\%\*\&;].*//;
- my $proto = prototype $name;
- my @args;
+ return $name, $proto;
+}
+
+sub recall {
+ my ($name, $proto) = _check_name shift;
+ my $call = $name . '(';
my @cr;
if (defined $proto) {
my $i = 0;
my $p = $2;
if ($1) {
my $r = _check_ref $_[$i], $p;
- push @args, join '', $sigils{$r}, '{$_[', $i, ']}';
+ $call .= $sigils{$r} . '{$_[' . $i . ']},';
} elsif ($p =~ /[\@\%]/) {
- push @args, join '', '@_[', $i, '..', (@_ - 1), ']';
+ $call .= '@_[' . $i . '..' . (@_ - 1) . ']';
last;
} elsif ($p =~ /\&/) {
push @cr, $_[$i];
- push @args, 'sub{&{$cr[' . $#cr . ']}}';
+ $call .= 'sub{&{$cr[' . $#cr . ']}},';
} elsif ($p eq '_' && $i >= @_) {
- push @args, '$_';
+ $call .= '$_,';
} else {
- push @args, '$_[' . $i . ']';
+ $call .= '$_[' . $i . '],';
}
++$i;
}
+ $call =~ s/,$//;
} else {
- @args = map '$_[' . $_ . ']', 0 .. @_ - 1;
+ $call .= join ',', map '$_[' . $_ . ']', 0 .. @_ - 1;
}
- my @ret = eval $name . '(' . join(',', @args) . ');';
+ $call .= ');';
+ my @ret = eval $call;
croak $@ if $@;
return @ret;
}
+=head2 C<wrap $name, %opts>
+
+Generates a wrapper that does the same thing as L</recall>, but specialized for a given function. This wrapper can be compiled once for all to avoid calling C<eval> at each run (like L</recall> does). You can still force the prototype by passing C<< { $name => $proto } >> as the first argument. Others arguments are seen as key / value pairs and tune the code generated by L</wrap>. Valid keys are :
+
+=over 4
+
+=item C<< ref => $func >>
+
+Specifies the function used in the generated code to test the reference type of scalars. Defaults to C<'ref'>. You may also want to use C<Scalar::Util::reftype>.
+
+=item C<< wrong_ref => $code >>
+
+The code executed when a reference of incorrect type is encountered. The result of this snippet is also the result of the generated code, hence it defaults to C<'undef'>. It's a good place to C<croak> or C<die> too.
+
+=item C<< sub => $bool >>
+
+Encloses the code into a C<sub { }> block. Default is true.
+
+=item C<< compile => $bool >>
+
+Makes L</wrap> compile the code generated and return the resulting code reference. Implies C<< sub => 1 >>. Be careful that in this case C<ref> must be a fully qualified function name. Defaults to false.
+
+=back
+
+This is how you make your own C<push> that pushes into array references :
+
+ my @a = (0 .. 2);
+ my $push = wrap 'CORE::push', compile => 1;
+ $push->(\@a, 3 .. 7); # returns 3 + 5 = 8, and @a now contains 0 .. 7
+
+=cut
+
+sub _wrap {
+ my ($name, $proto, $i, $args, $cr, $opts) = @_;
+ if ($proto =~ /(\\?)(\[[^\]]+\]|[^\];])(.*)/g) {
+ my ($ref, $p) = ($1, $2);
+ $proto = $3;
+ $p = $1 if $p =~ /^\[([^\]]+)\]/;
+ my $cur = '$_[' . $i . ']';
+ if ($ref) {
+ if (length $p > 1) {
+ return 'my $r = ' . $opts->{ref} . '(' . $cur . '); '
+ . join ' els',
+ map( {
+ "if (\$r eq '" . $reftypes{$_} ."') { "
+ . _wrap($name, $proto, ($i + 1),
+ $args . $_ . '{' . $cur . '}, ',
+ $cr, $opts)
+ . ' }'
+ } split //, $p),
+ 'e { ' . $opts->{wrong_ref} . ' }'
+ } else {
+ $args .= $p . '{' . $cur . '}, ';
+ }
+ } elsif ($p =~ /[\@\%]/) {
+ $args .= '@_[' . $i . '..$#_]';
+ } elsif ($p =~ /\&/) {
+ my %h = do { my $c; map { $_ => $c++ } @$cr };
+ my $j;
+ if (not exists $h{$i}) {
+ push @$cr, $i;
+ $j = $#{$cr};
+ } else {
+ $j = int $h{$i};
+ }
+ $args .= 'sub{&{$c[' . $j . ']}}, ';
+ } elsif ($p eq '_') {
+ $args .= '((@_ > ' . $i . ') ? ' . $cur . ' : $_), ';
+ } else {
+ $args .= $cur . ', ';
+ }
+ return _wrap($name, $proto, ($i + 1), $args, $cr, $opts);
+ } else {
+ $args =~ s/,\s*$//;
+ return $name . '(' . $args . ')';
+ }
+}
+
+sub wrap {
+ my ($name, $proto) = _check_name shift;
+ croak 'Optional arguments must be passed as key => value pairs' if @_ % 2;
+ my %opts = @_;
+ $opts{ref} ||= 'ref';
+ $opts{sub} = 1 if not exists $opts{sub} or $opts{compile};
+ $opts{wrong_ref} = 'undef' if not defined $opts{wrong_ref};
+ my @cr;
+ my $call;
+ if (defined $proto) {
+ $call = _wrap $name, $proto, 0, '', \@cr, \%opts;
+ } else {
+ $call = _wrap $name, '', 0, '@_';
+ }
+ if (@cr) {
+ $call = 'my @c; '
+ . join('', map { 'push @c, $_[' . $_ . ']; ' } @cr)
+ . $call
+ }
+ $call = '{ ' . $call . ' }';
+ $call = 'sub ' . $call if $opts{sub};
+ if ($opts{compile}) {
+ $call = eval $call;
+ croak $@ if $@;
+ }
+ return $call;
+}
+
=head1 EXPORT
-The functions L</flatten> and L</recall> are only exported on request, either by providing their name or by the C<':funcs'> and C<':all'> tags.
+The functions L</flatten>, L</recall> and L</wrap> are only exported on request, either by providing their name or by the C<':funcs'> and C<':all'> tags.
=cut
@EXPORT = ();
%EXPORT_TAGS = (
- 'funcs' => [ qw/flatten recall/ ]
+ 'funcs' => [ qw/flatten recall wrap/ ]
);
@EXPORT_OK = map { @$_ } values %EXPORT_TAGS;
$EXPORT_TAGS{'all'} = [ @EXPORT_OK ];
Vincent Pit, C<< <perl at profvince.com> >>, L<http://www.profvince.com>.
-You can contact me by mail or on #perl @ FreeNode (vincent or Prof_Vince).
+You can contact me by mail or on C<irc.perl.org> (vincent).
=head1 BUGS
projects / perl / modules / Sub-Prototype-Util.git / blobdiff