You Need a Tool to Search Inside Your Standard Library

Today, programming languages have so much big standard libraries that it’s a pain to know everything: one of my programming teacher (a C and C++ addict) told me that the thing that hurts him with Java and .Net was the huge standard library and the difficulty of having a good knowledge of these toolkits. Maybe he was not wrong, and that documentation is sometimes a kind of unusable garbage, or even disappearing (for example when Oracle moved everything about Java to random locations).

However, it can be a bigger pain to re-write something that already exists than to learn and build easy tools to search for informations inside your standard library. A tool that allow to search for common modules names (like URI manipulation or JSON or IO, anything), it’s sometime too long to search on metacpan.org and on perl.org when you just need to use something in your code. This problem comes also from my bad (human) memory, I can’t remember all these tools that I used only a few times. I can even less remember oneliners whith more than 20 chars…

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perl -MExtUtils::Installed -MData::Dumper -e  'my ($inst) = ExtUtils::Installed->new(); print Dumper($inst->modules());'

` … is maybe a possible solution to search for modules, but it is hard to remember.

I wondered how I could display all the modules installed on my machine (most of the time, you don’t need a new module). So after a search, I found something that makes possible to display all the modules on my machine (standard or user-installed modules, AKA @INC content).

The only thing that were missing was a kind of searchability. As I was too lazy and shy to try to extend App::Module::Lister, I’ve just wrote some configuration in my .bashrc.

First install App::Module::Lister…

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$ cpanm App::Module::Lister  
Searching App::Module::Lister on cpanmetadb ...
Fetching http://www.cpan.org/authors/id/B/BD/BDFOY/App-Module-Lister-0.15.tar.gz
Building and testing App-Module-Lister-0.15
All tests successful.
Successfully installed App-Module-Lister-0.15
1 distribution installed

…then in .bashrc, add the following…

Allow to search inside Perl @INC and find installed modules. Note that it can take one argument (search string)
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function plister () {
  # Get the current position to go back into it  after the script run
  INITIAL_POSITION=$(PWD)
  PLISTER_HOME=$HOME/perl5/lib/perl5/App/Module/
  # Have to move because of limitation of the module
  # See http://search.cpan.org/dist/App-Module-Lister/lib/App/Module/Lister.pm#TO_DO
  cd ${PLISTER_HOME}

  # Search with a pattern
  if [ $1 ] ; then
    # \grep "unalias" grep if you got some
    perl Lister.pm | \grep --ignore-case $1
    echo "Searched with App::Module::Lister with pattern $1"
  # Search all modules installed
  else
    perl Lister.pm
    echo "Searched with App::Module::Lister with no pattern"
  fi
  cd ${INITIAL_POSITION}
}

source your .bashrc, and you now got a nice modules local search-engine based on App::Module::Lister abilities.

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$ plister Module::Starter
Module::Starter   1.60
Module::Starter::Smart    0.0.4
Module::Starter::Simple   1.60
Module::Starter::App  1.60
Module::Starter::BuilderSet   1.60
Module::Starter::Plugin::Template 1.60
Searched with App::Module::Lister with pattern Module::Starter

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