JezK
Edit File: overload.pm
package overload; use strict; no strict 'refs'; no warnings 'experimental::builtin'; our $VERSION = '1.35'; our %ops = ( with_assign => "+ - * / % ** << >> x .", assign => "+= -= *= /= %= **= <<= >>= x= .=", num_comparison => "< <= > >= == !=", '3way_comparison' => "<=> cmp", str_comparison => "lt le gt ge eq ne", binary => '& &= | |= ^ ^= &. &.= |. |.= ^. ^.=', unary => "neg ! ~ ~.", mutators => '++ --', func => "atan2 cos sin exp abs log sqrt int", conversion => 'bool "" 0+ qr', iterators => '<>', filetest => "-X", dereferencing => '${} @{} %{} &{} *{}', matching => '~~', special => 'nomethod fallback =', ); my %ops_seen; @ops_seen{ map split(/ /), values %ops } = (); sub nil {} sub OVERLOAD { my $package = shift; my %arg = @_; my $sub; *{$package . "::(("} = \&nil; # Make it findable via fetchmethod. for (keys %arg) { if ($_ eq 'fallback') { for my $sym (*{$package . "::()"}) { *$sym = \&nil; # Make it findable via fetchmethod. $$sym = $arg{$_}; } } else { warnings::warnif("overload arg '$_' is invalid") unless exists $ops_seen{$_}; $sub = $arg{$_}; if (not ref $sub) { $ {$package . "::(" . $_} = $sub; $sub = \&nil; } #print STDERR "Setting '$ {'package'}::\cO$_' to \\&'$sub'.\n"; *{$package . "::(" . $_} = \&{ $sub }; } } } sub import { my $package = (caller())[0]; # *{$package . "::OVERLOAD"} = \&OVERLOAD; shift; $package->overload::OVERLOAD(@_); } sub unimport { my $package = (caller())[0]; shift; *{$package . "::(("} = \&nil; for (@_) { warnings::warnif("overload arg '$_' is invalid") unless exists $ops_seen{$_}; delete $ {$package . "::"}{$_ eq 'fallback' ? '()' : "(" .$_}; } } sub Overloaded { my $package = shift; $package = ref $package if ref $package; mycan ($package, '()') || mycan ($package, '(('); } sub ov_method { my $globref = shift; return undef unless $globref; my $sub = \&{*$globref}; no overloading; return $sub if $sub != \&nil; return shift->can($ {*$globref}); } sub OverloadedStringify { my $package = shift; $package = ref $package if ref $package; #$package->can('(""') ov_method mycan($package, '(""'), $package or ov_method mycan($package, '(0+'), $package or ov_method mycan($package, '(bool'), $package or ov_method mycan($package, '(nomethod'), $package; } sub Method { my $package = shift; if(ref $package) { local $@; local $!; $package = builtin::blessed($package); return undef if !defined $package; } #my $meth = $package->can('(' . shift); ov_method mycan($package, '(' . shift), $package; #return $meth if $meth ne \&nil; #return $ {*{$meth}}; } sub AddrRef { no overloading; "$_[0]"; } *StrVal = *AddrRef; sub mycan { # Real can would leave stubs. my ($package, $meth) = @_; local $@; local $!; require mro; my $mro = mro::get_linear_isa($package); foreach my $p (@$mro) { my $fqmeth = $p . q{::} . $meth; return \*{$fqmeth} if defined &{$fqmeth}; } return undef; } my %constants = ( 'integer' => 0x1000, # HINT_NEW_INTEGER 'float' => 0x2000, # HINT_NEW_FLOAT 'binary' => 0x4000, # HINT_NEW_BINARY 'q' => 0x8000, # HINT_NEW_STRING 'qr' => 0x10000, # HINT_NEW_RE ); use warnings::register; sub constant { # Arguments: what, sub while (@_) { if (@_ == 1) { warnings::warnif ("Odd number of arguments for overload::constant"); last; } elsif (!exists $constants {$_ [0]}) { warnings::warnif ("'$_[0]' is not an overloadable type"); } elsif (!ref $_ [1] || "$_[1]" !~ /(^|=)CODE\(0x[0-9a-f]+\)$/) { # Can't use C<ref $_[1] eq "CODE"> above as code references can be # blessed, and C<ref> would return the package the ref is blessed into. if (warnings::enabled) { $_ [1] = "undef" unless defined $_ [1]; warnings::warn ("'$_[1]' is not a code reference"); } } else { $^H{$_[0]} = $_[1]; $^H |= $constants{$_[0]}; } shift, shift; } } sub remove_constant { # Arguments: what, sub while (@_) { delete $^H{$_[0]}; $^H &= ~ $constants{$_[0]}; shift, shift; } } 1; __END__