Looks into the given $library_dir and imports the functions in all
   files with the extension .pl (non-recursively). Each file must have the
   name of its main function to be imported to Vim-space.

   To have good start-up time and to avoid loading all dependencies for
   all functions, the different files aren't sourced at start-up, but are
   rather using the autocmd function of Vim to trigger the loading of
   those files only if used.

   E.g.,

       # in ~/.vim/vimx/perlweekly/PWGetInfo.pl
       use Vim::X;

       use LWP::UserAgent;
       use Web::Query;
       use Escape::Houdini;

       sub PWGetInfo :Vim() {
           ...;
       }

       # in .vimrc
       perl use Vim::X;

       autocmd BufNewFile,BufRead **/perlweekly/src/*.mkd
                   \ perl Vim::X::load_function_dir('~/.vim/vimx/perlweekly')
       autocmd BufNewFile,BufRead **/perlweekly/src/*.mkd
                   \ map <leader>pw :call PWGetInfo()<CR>

   Like load_function_dir, but if it finds files with the exension .pvim,
   it'll also source them as vimL files at load-time, allowing to define
   both the Perl bindings and the vim macros in the same file. Note that,
   magically, the Perl code will still only be compiled if the function is
   invoked.

   For that special type of magic to happen, the .pvim files must follow a
   certain pattern to be able to live their double-life as Perl scripts
   and vim file:

       ""; <<'finish';

       " your vim code goes here

       finish

       # the Perl code goes here

   When sourced as a vim script, the first line is considered a comment
   and ignored, and the rest is read until it hits finish, which cause Vim
   to stop reading the file. When read as a Perl file, the first line
   contains a heredoc that makes all the Vim code into an unused string,
   so basically ignore it in a fancy way.

   For example, the snippet for load_function_dir could be rewritten as
   such:

       # in ~/.vim/vimx/perlweekly/PWGetInfo.pvim
       ""; <<'finish';

           map <leader>pw :call PWGetInfo()<CR>

       finish

       use Vim::X;

       use LWP::UserAgent;
       use Web::Query;
       use Escape::Houdini;

       sub PWGetInfo :Vim() {
           ...;
       }

       # in .vimrc
       perl use Vim::X;

       autocmd BufNewFile,BufRead **/perlweekly/src/*.mkd
                   \ perl Vim::X::source_function_dir('~/.vim/vimx/perlweekly')

   Loads the code within $file_path under the namespace
   Vim::X::Function::$name, where name is the basename of the $file_path,
   minus the .pl/.pvim extension. Not that useful by itself, but used by
   load_function_dir.

   Display the strings of @text concatenated as a vim message.

       vim_msg "Hello from Perl";

   Returns the Vim::X::Buffer object associated with the $ith buffer. If
   $i is not given or set to '0', it returns the current buffer.

   Returns the file associated with the current buffer as a Path::Tiny
   object. If $local is true the path will be relative to the directory
   where vim was launched, otherwise it'll be absolute.

   Returns the Vim::X::Line objects for the lines in @indexes of the
   current buffer. If no index is given, returns all the lines of the
   buffer.

   Returns the Vim::X::Line object for line $index of the current buffer.
   If $index is not given, returns the line at the cursor.

   Appends the given lines after the line under the cursor.

   If carriage returns are present in the lines, they will be split in
   consequence.

   Evals the given @expressions and returns their results.

   Returns a Vim::X::Range object for the given lines, or single line, in
   the current buffer. The lines can be passed as indexes, or Vim::X::Line
   objects.

   If no line whatsoever is passed, the range will be the one on which the
   command has been called (i.e.: :afirstline and a:lastline).

   Run the given 'ex' commands and return their results.

       vim_command 'normal 10G', 'normal iHi there!';

   Calls the vim-space function $function with the provided arguments.

       vim_call( 'SetVersion', '1.23' )

       # equivalent of doing
       #    :call SetVersion( '1.23' )
       # in vim

   Returns the expansion of the passed expression(s).

       my $current_file = vim_expand( '%' );
       my ( $local, $absolute) = vim_expand( '%', '%:p' );

   Prompts the user for some value. The arguments are the same as for
   vim's own input.

   Returns the Vim::X::Window associated with the $ith window. If $i is
   not provided or is zero, returns the object for the current window.

   Returns the Vim::X::Cursor associated with the position of the cursor
   in the current window.

   Deletes the given lines from the current buffer.

SYNOPSIS

       package Vim::X::Plugin::MostUsedVariable;

       use strict;
       use warnings;

       use Vim::X;

       sub MostUsedVariable :Vim {
           my %var;

           for my $line ( vim_lines ) {
               $var{$1}++ while $line =~ /[$@%](\w+)/g;
           }

           my ( $most_used ) = reverse sort { $var{$a} <=> $var{$b} } keys %var;

           vim_msg "variable name $most_used used $var{$most_used} times";
       }

   and then in your .vimrc:

       perl push @INC, '/path/to/plugin/lib';
       perl use Vim::X::Plugin::MostUsedVariable;

       map <leader>m :call MostUsedVariable()

DESCRIPTION

   Vim::X provides two tools to make writing Perl functions for Vim a
   little easier: it auto-exports functions tagged by the attribute :Vim
   in Vim-space, and it defines a slew of helper functions and objects
   that are a little more Do What I Mean than the VIM API module that
   comes with Vim itself.

   Obviously, for this module to work, Vim has to be compiled with Perl
   interpreter support.

Import Perl function in Vim-space

   Function labeled with the :Vim attribute are automatically exported to
   Vim.

   The :Vim attribute accepts two optional parameters: args and range.

 :Vim(args)

   If args is present, the function will be exported expecting arguments,
   that will be passed to the function via the usual @_ way.

       sub Howdie :Vim(args) {
           vim_msg( "Hi there, ", $_[0] );
       }

       # and then in vim:
       call Howdie("buddy")

 :Vim(range)

   If range is present, the function will be called only once when invoked
   over a range, instead than once per line (which is the default
   behavior).

       sub ReverseLines :Vim(range) {
           my @lines = reverse map { "$_" } vim_range();
           for my $line ( vim_range ) {
               $line <<= pop @lines;
           }
       }

       # and then in vim:
       :5,15 call ReverseLines()

 Loading libraries

   If your collection of functions is growing, load_function_dir() can
   help with their management. See that function below for more details.

SEE ALSO

   The original blog entry: http://techblog.babyl.ca/entry/vim-x

 CONTRIBUTORS

   Hernan Lopes

POD ERRORS

   Hey! The above document had some coding errors, which are explained
   below:

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