in reply to Re^2: Best way to keep script with generated output
in thread Best way to keep script with generated output

Can you include a literal newline inside the double quotes? That would allow you to use perl -x: 
<not> <gonna> <happen> : "
#!perl

.
. This is the script
.

__END__
"

.
. This is the actual file
.

[download]

So what would the script look like? How about 

local $^I = '~';
local @ARGV = __FILE__;

my $seen_data;

while (<>) {
    if (!$seen_data) {
        $seen_data = $_ eq qq{__END__\n};
        next;
    }

    ... change $_ as desired ...
}
continue
{
    print;
}

[download]

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Re^4: Best way to keep script with generated output
by benizi (Hermit) on Dec 09, 2009 at 03:10 UTC

    Huh. Cool. Yeah, that would work (via perl -x ~/.XCompose-ordering). Apparently there aren't any ill effects from even adding the following to .XCompose-ordering:

    "
#!perl -i.bak
@ARGV = ($0);
while (<>) {
    $end = 1 if /^__END__/;
    print if $end < 2;
    $end++ if /^"/ and $end;
    if (eof) {
        open my $f, "</usr/share/X11/locale/$ENV{LANG}/Compose" or die
+ "<$!";
        print for <$f>; # manipulate the line here
        close $f;
    }
}
__END__
"
# normal lines start here
# etc. etc.

    [download]

    But I suspect this is just a consequence of .XCompose files just ignoring ill-formed lines. (and not because it accepts multi-line strings -- note that I embedded several double-quotes.)

    Another interesting approach I tried was to simply add the following header:

    #!/bin/env updater
# perl -lanwe '(...the script from before...)' inputfile
# ...
# the normal output...
# ...

    [download]

    ~/bin/updater was:

    #!/usr/bin/perl
use strict;
use warnings;
my $script = '';
my $out = '';
my ($file) = @ARGV;
while (<>) {
    next unless s/^(#\s*)//;
    $script .= $_ unless $. == 1;
    $out .= "$1$_";
}
open STDOUT, '>', $file;
print $out;
open my $pipe, "| $ENV{SHELL}";
print $pipe $script;
close $pipe;

    [download]

    (NB. this doesn't make a backup like the other way.) That way, I can make .XCompose-ordering itself executable, and then simply run it to regenerate it. But, it has the advantage that it works for any file format that uses '#' comments.

[reply]
[d/l]
[select]
      But then you need to hardcode your own name into the file. I specifically avoided doing that. It's your call if that matters to you.
[reply]

        I don't follow. What name am I hard-coding? The "/usr/share/X11/locale/$ENV{LANG}/Compose" file is an input to the script. It's not the file being generated (~/.XCompose-ordering). I don't see what else is hard-coded.

[reply]
[d/l]

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