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#! /usr/local/bin/perl -sw
# RECURSIVE #includes DURING A RECURSIVE DESCENT
use Parse::RecDescent;
sub loadfile($)
{
open FILE, $_[0] or die "Couldn't find included file: $_[0]\n";
my $contents = <FILE>;
close FILE;
return $contents;
}
%macro = ();
sub demacro($)
{
my $text = shift;
while (($macro,$defn) = each %macro )
{
$text =~ s/$macro/$defn/;
}
return $text;
}
$grammar =
q{
file : line(s)
line : include
| macrodef
| linedir
{ $thisline = $item[1]; }
| codeline
{ print "found: [$item[1]] at $thisline\n" }
include : '#include' filename
{
print "pre: [$text] at $thisline\n";
$text = ::loadfile($item[-1]) . $text;
Parse::RecDescent::LineCounter::resync $thisline;
print "post: [$text] at $thisline\n";
}
filename : '"' m#[a-z0-9_./-]+#i '"'
{ $return = $item[-2] }
| '<' m#[a-z0-9_./-]+#i '>'
{ $return = $item[-2] }
macrodef : '#define' /[a-z]\w*/i /.*/
{ $::macro{$item[-2]} = $item[-1] }
linedir: '#line' /\d+/
codeline : /.*\n/
{ $return = ::demacro($item[-1]); }
};
$parse = new Parse::RecDescent ($grammar);
undef $/;
$reinput = $input = <>;
$parse->file($input) or die "Bad file! No biscuit!\n";
$parse->file($reinput) or die "Bad file! No biscuit!\n";
|
