use strict;
use warnings;
use Shell::Parser;
use Data::Dumper;


sub parse_shellscript_from_fh {
  my ($fh) = @_;
  my %vars;

  my $parser = new Shell::Parser syntax => 'bash',
    handlers => {
		 assign => sub {
		   my ($self, %args)  = @_;
		   my ($name, $value) =
		     $args{token} =~ /^\s*(\w+)\s*=\s*\"(.*)\"\s*$/s;

		   if ( defined $value ) {
		     #-- multi-line/array? $value =~ s/\n//msg;
		     $vars{$name} = $value;
		   } else {
		     warn "No value for variable ", ($name//'?'), "\n";
		   }
		 }
		};

  #-- parsing
  my $text = join("", <$fh>);
  $parser->parse(  $text );
  $parser->eof;


  #-- rudimentary variable interpolation
  my $max_passes = 5;
  my $not_substituted;
  for (1 .. $max_passes ) {
    $not_substituted = 0;
    foreach my $varname ( keys %vars ) {
      $vars{$varname} =~ s|\$(\w+)| $vars{$1} // do{ "\$$1" } |ge;
      $not_substituted += $vars{$varname} =~ tr/$/$/;
    }
    last unless $not_substituted;
  }

  die "Recursion or too few parses ... " if $not_substituted;

  return \%vars;
}



print "Vars: ", Dumper( parse_shellscript_from_fh( *DATA ) ), "\n";



__DATA__
A="foo"
B="some other data"
C="appending $A"
D="
  some list
  with more data
  and $B
"

X=<<EOF
  does not work there
EOF

Y=`echo fails`


##</code><code>##

No value for variable ?
No value for variable ?
Vars: $VAR1 = {
          'A' => 'foo',
          'D' => '
  some list
  with more data
  and some other data
',
          'C' => 'appending foo',
          'B' => 'some other data'
        };