App-Cheats

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cheats.txt  view on Meta::CPAN

## Perl Modules - Carp
#############################################################

# Show a stack trace in perl.
perl -MCarp=longmess -E 'sub fun1{ fun2("TO FUN2") } sub fun2{ say longmess } fun1("TO FUN1")'

# Show a stack trace in perl. (Carp uses a similar approach).
# @DB::args is set (for a scope) when this command is run (some magic).
{
   package DB;
   my @caller = caller($scope);
   () = caller($scope);             # Same thing (to invoke LIST context).
}
perl -E 'sub fun1{ fun2("TO FUN2") } sub fun2{ my $scope = 0; while(my @caller = caller($scope)){ {package DB; () = caller($scope)} say "@caller[1,2,3,4] - (@DB::args)"; $scope++ }} fun1("TO FUN1")'


#############################################################
## Perl Modules - Carton
#############################################################

# Keep track of the installed modules in a local directory by making a
# virtual environment. Like virtualenv and requirements.txt, but for Perl.
cpanm Carton

cheats.txt  view on Meta::CPAN

#############################################################

# WhoAmI to all functions in a class.
+ #!/usr/bin/perl
+
+ package Subs::Trace;
+
+ use v5.32;
+
+ sub import {
+   my $pkg = caller();
+
+   INIT {
+     no strict 'refs';
+
+     for my $func (sort keys %{"${pkg}::"}) {
+         my $code = ${"${pkg}::"}{$func}->*{CODE};
+         next if not $code;
+
+         ${"${pkg}::"}{$func}->** = sub {
+             say "-> $pkg\::$func";

cheats.txt  view on Meta::CPAN

#############################################################
## Perl Modules - Tie::Watch
#############################################################

# Tie Watch. OOP interface that hides making packages for tied variables
perl -MTie::Watch -le 'my $v=1; Tie::Watch->new(-variable => \$v, -fetch => sub{my $s=shift; $v=$s->Fetch; $s->Store($v+1); $v}); print $v; print $v; print $v'

# Check when a variable is updated. (watcher)
perl -MTie::Watch -Mojo -le 'my $h={a => [1..2]}; say r $h; Tie::Watch->new( -variable => \$h->{a}, -store => sub{my ($s,$v) = @_; $s->Store($v); my $Scope = 0; while( my ($Pkg,$Line) = caller(++$Scope) ){ say "$Pkg:$Line" } }); sub func{$h->{a}=456}...

# Check when a variable is updated. (watcher)
use Tie::Watch;
Tie::Watch->new(
   -variable => \$Self->{Cache}->{ $Param{Type} }->{ $Param{Key} },
   -store    => sub{
       my ($S,$Value) = @_;
       $S->Store($Value);
       my $Scope = 0;
       my $Limit = 5;
       while( my ($Package,$Line) = (caller(++$Scope))[0,2] ){
          next if $Package =~ /\ATie::/;
          say "* Store: $Package line $Line";
          last if $Scope >= $Limit;
       }
   },
);

# Problem using Tie::Watch with Storable::dclone.
perl -MData::Tie::Watch -MStorable -e '$data = {}; $obj = Data::Tie::Watch->new( -variable => $data ); Storable::dclone($data)'
perl -MData::Tie::Watch -MStorable -e '$data = 111; $obj = Data::Tie::Watch->new( -variable => \$data ); Storable::dclone(\$data)'

cheats.txt  view on Meta::CPAN

#############################################################

# Example of using a multiline string in Vim
#
+ " Perl Data Dumper and other useful features all in one mapping.
+ function PerlDev()
+    let l:PERL_DEV = "
+       \\nuse v5.32;
+       \\nuse Mojo::Util qw(dumper);
+       \\nuse Carp       qw( croak confess carp cluck );
+       \\nsub WhoAmI { say '--> ' . (caller(1))[3] }
+       \\nsay 'var: ', dumper $var;
+       \\n$Self->HandleException('message'); # New    - Test/*
+       \\n$Selenium->HandleError('message'); # Legacy - script/*
+       \\n
+       \\n"
+
+    put =l:PERL_DEV
+ endfunction
+
+ nnoremap <leader>r :call PerlDev()<CR>