in reply to Parsing variables from login scripts

It's not too difficult... you just need split and a regex check. Something like the following is untested but conceptually fairly sound: 
while (<INPUT>) {
    chomp;
    my ($var, $value) = split(/\s*=\s+/, $_, 2);
    if ($value =~ s/^\$(\w+)//) {
#        $value .= $env_var{$1} || '';
        $value = $env_var{$1} . $value;
    }
    $env_var{$var} = $value;
}

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You could make that shorter, but you could also add better checking to make it better. Jellybean actually does this in Jellybean::Config, so I know I've written it correctly at least once before.

Update: Don't work and post. Fastolfe is correct, and I've updated my code to work.

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RE: Re: Parsing variables from login scripts
by eLore (Hermit) on Jul 28, 2000 at 18:55 UTC
    I've been working way too many hours to see this clearly. Here's what's not working so well, so far... Ok, let's see if I can format this correctly: 
    ___DATA___
MY_DIR=~/temp/module
export MY_DIR
MY_BIN=$MY_DIR/bin
MY_DATA=$MY_DIR/data
export MY_BIN MY_DATA

__temp.pl__
#! /usr/local/bin/perl
require "testpack.pm";
testpack::import();
print "DIR $DIR\n";

__testpack.pm__
package testpack;
sub import {
  $conf_file = "conf.sh";
  open (FILE, $conf_file) || die "Cant open file. \n";
  while (<FILE>) {
    if (! (/^\W/ || /^export/)) {  # ign. cmnts & ws
      chomp;

      print "$_\n";
      my ($var, $value) = split(/\s*=\s+/, $_, 2);
      if ($value =~ s/^\$(\w+)//) {
        $value .= $env_var{$1} || '';
      }
      $env_var{$var} = $value;
      my ($caller_package) = caller;
      *{"${caller_package}::${var}"} = $value;
    } # end if
  } # end while
} # END import() definition

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[d/l]
      Your split doesn't match your data -- the whitespace before the = is optional (zero or more instances) but required after the sign (one or more instances). Change the + to a * and it will probably work better.

      You might put a debugging line after the split, just to see what's in $var and $value: print "\$var is ->$var<-\t\$value is ->$value<-\n"; Besides that, I had things backwards in the original version of my code. Try this instead: $value = $env_var{$1} . $value; That way, it won't go in the wrong place. Oops!

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RE: Re: Parsing variables from login scripts
by Fastolfe (Vicar) on Jul 28, 2000 at 19:34 UTC
    Shell-style variable interpolation has been discussed in recent nodes. The one you have above won't work at all like you seem to expect.

    PATH = /someplace
PATH = $PATH:/somewhere/else

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    In this case, $env_var{PATH} would equal ":/somewhere/else/someplace".

    I'm afraid I can't find the original thread, but a fairly robust regular expression looked something like this: 

    $value =~ s/$({?)(\w+)(?(1)})/$env_var{$2}/eg;

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    This would interpolate stuff like $PATH, ${PATH}, etc.
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