Can you tell Vim to open a different file than the one passed on the commandline or to :e?

Question

I want to teach Vim how to open Perl 5 modules from names like File::Find. I already have a wrapper script written in Perl 5 that handles the commandline (see below), but I would like to be able to say things like :tabe File::Find and have it really execute :tabe /home/cowens/apps/perlbrew/perls/perl-5.14.0/lib/5.14.0/File/Find.pm.

My current plan is to somehow use autocmd BufNewFile and/or autocmd BufPreRead, but I can't figure out how to switch the file name.

#!/usr/bin/perl

use strict;
use warnings;

my @files = @ARGV;
for my $file (@files) {
    next if -f $file; #skip files that really exist

    #convert from module name to module file
    (my $module = $file) =~ s{::}{/}g;
    $module .= ".pm";

    #look for module in the include paths
    for my $dir (@INC) {
        my $candidate = "$dir/$module";
        if (-f $candidate) {
            $file = $candidate;
            last;
        }
    }
}

#replace this script with vim
exec "vim", "-p", @files;

Answer 1

Doing

:verbose au BufReadCmd

Will tell you how other types of plugins do this (e.g. zip, netrw, fugitive). Sample output that should give you plenty of ideas:

zip  BufReadCmd
    zipfile:* call zip#Read(expand("<amatch>"), 1)
    Last set from C:\Program Files\Vim\vim73\plugin\zipPlugin.vim
    *.zip     call zip#Browse(expand("<amatch>"))
    Last set from C:\Program Files\Vim\vim73\plugin\zipPlugin.vim

Network  BufReadCmd
    ftp://*   exe "silent doau BufReadPre ".fnameescape(expand("<amatch>"))|call netrw#Nread(2,expand("<amatch>"))|exe "silent doau BufReadPost ".fnameescape(expand("<amatch>"))
    Last set from C:\Program Files\Vim\vim73\plugin\netrwPlugin.vim
    http://*  exe "silent doau BufReadPre ".fnameescape(expand("<amatch>"))|call netrw#Nread(2,expand("<amatch>"))|exe "silent doau BufReadPost ".fnameescape(expand("<amatch>"))
    Last set from C:\Program Files\Vim\vim73\plugin\netrwPlugin.vim

fugitive_files  BufReadCmd
    *.git/index
              exe s:BufReadIndex()
    Last set from C:\Program Files\Vim\vimfiles\plugin\fugitive.vim
    *.git/*index*.lock
              exe s:BufReadIndex()
    Last set from C:\Program Files\Vim\vimfiles\plugin\fugitive.vim
    fugitive://**//[0-3]/**
              exe s:BufReadIndexFile()
    Last set from C:\Program Files\Vim\vimfiles\plugin\fugitive.vim
    fugitive://**//[0-9a-f][0-9a-f]*
              exe s:BufReadObject()
    Last set from C:\Program Files\Vim\vimfiles\plugin\fugitive.vim

Answer 2

Consider using ctags. If you're able to run the ctags process over your source code, you should be able to get to a point where you simply do:

vim -t File::Find

Vim has information about this (:help vim) I think ctags probably goes well beyond what you're trying to do, allowing you to jump from the middle of one source file to the original function definition in another.