#!/usr/local/bin/perl
# 
# pull_quotes -- tom christiansen, tchrist@convex.com
#
################################################################################
sub show_quotes {
    local($string, $qchars) = @_;
    local($i) = $[;
    local($_);

    local(@list) = &pull_quotes($string,$qchars);

    $qchars =~ s/(.)(.)/`$1'...`$2'/;

    print "Extracted ", 0+@list, " ", $qchars, " quote", 
	(@list != 1)?'s':'', "\n";
    #print "Extracted ", 0+@list, " ", $qchars, " quote", 
	#(@list != 1)?'s':'', " from:<<", $_[0]. ">>\n";

    for (@list) {
	print "Quote #$i is <<", $_, ">>\n";
	$i++;
    } 
    print "\n";
} 


################################################################################
sub pull_quotes { # pull_quotes($string, $quotchars) => @quotestrings
    local($_, $qchars) = @_;

    local($xlate);

    if ($qchars =~ tr/\173\175/\373\375/) {
	$xlate++;
	tr/\173\175/\373\375/;
    } 

    local($qL, $qR); 		# left and right quote chars, like `' or ()
    local($quote_level);	# current quote level
    local($max_quote);		# deepest we've gotten
    local($qstring);		# tmp space for quote
    local(@quotes);		# list of quotes to return
    local($d) = '\$';		# not sure why this must be here
    local($b) = '\\';		# nor this
    local(@done);		# which quotes we've finished so far

    die "need two just quote chars" if length($qchars) != 2;

    $qL = substr($qchars, 0, 1);
    $qR = substr($qchars, 1, 1);

    s/\\(.)/"\201".ord($1)."\202"/eg;   # protect from backslashes

    $max_quote = $quote_level = $[-1;

    while ( /[$qchars]/ ) {
	if ($& eq $qL) {
	    do { ++$quote_level; } while $done[$quote_level];
	    s/$b$qL/\${QL${quote_level}}/;
	    $max_quote = $quote_level if $max_quote < $quote_level;
	} elsif ($& eq $qR) {
	    s/$b$qR/\${QR${quote_level}}/;
	    $done[$quote_level]++;
	    do { --$quote_level; } while $done[$quote_level];
	} else { 
	    die "unexpected quot char: $&";
	}
    } 
    for ($quote_level = $[; $quote_level <= $max_quote; $quote_level++) {
	($qstring) = /${d}\{QL$quote_level\}([^\000]*)${d}\{QR$quote_level}/;
	$qstring =~ s/\${QL\d+\}/$qL/g;
	$qstring =~ s/\${QR\d+\}/$qR/g;
	$qstring =~ s/\201(\d+)\202/pack('C',$1)/eg;
	$quotes[$quote_level] = $qstring;
    } 
    grep (tr/\373\375/\173\175/, @quotes) if $xlate;
    @quotes;
} 

################################################################################
################################################################################
################################################################################
################################################################################
################################################################################

# MAIN STARTS HERE


&show_quotes(<<__END__, '()');

 param(zzz = (var0));

 param(yyy = ((var1=xx), var2(xx), (var3 = xx),
             var4=xx, var5=xx, etc. etc.)) ;
 
 param(yyy = ((var1=xx), var2(xx), (var3 = xx),
             var4=xx, var5=xx, etc. etc.))
 
__END__