#!/usr/bin/perl


# *Rewrites* files:
#
# % some string \
# % other string
#
# ===>>
# % some string other string

use warnings;
use strict;

my $file = $ARGV[0];

open(FH, '<', $file) || die "open $file: $!";
my @lines = <FH>;
close(FH);

open(FH, '>', $file) || die "open $file: $!";
my $concat = 0;
foreach (@lines) {

    if ($concat) {
        s/^\s*%/ /;
    }

    if (s/\\+$//) {
        chomp;
        $concat = 1;
    } else {
        $concat = 0;
    }

    print FH;
}
close(FH);