#fmtsub  -  perform substitutions

#  Constants

sub fmt {

	local(@data);
	local($tmpl) = shift;
	if ($tmpl) { local(@tmpl) = @$tmpl }
	local($data) = shift;
	if ( $data ) { @data = @$data }
	local($rslt)="";
	local(@rlst)=();


	local($look_keywd)=1;
	local($n_key)=0;
	local($keywd,$line,$value);
	undef(%key);

	foreach (@data) 
	{
		#
		#  look for lines of the form  :key:
		#
		if ($look_keywd)
		{ if(/:(\w+):/)
			{	$keywd=$1;
				$look_keywd=0;
				s/:\w+://;
				s/^[ \t]*//;
				s/[ \t]*$//;
				s/^\n$//;
				$line=$_;
				next;
			}
		}
		else
		{ if(/:(\w+):/)
			{	$look_keywd=1;
				chop($line);
				$key{$keywd} = $line;
				redo;
			}
			$line=$line . $_;
		}
	}
	# last keyword
	chop($line);
	$key{$keywd} = $line;

	foreach (@tmpl) 
	{
		if (/#/) {
			while(1)
			{
				last if(! /#([^#]+)#/);
				if (defined ($value=$key{$1})) {
					s/#$1#/$value/e;
					next;
				} elsif ( s/^([^#]*)#\w+#/\1/ ) { 
					next;
				} else {
					last if (! /(.*#.*)(#.*#.*)/);
					$rslt .=  $1;
					$_ =$2 . "\n";
				}
			}
		}
		$rslt .=  $_;
		push(@rslt,$_);
	}
	return wantarray ? @rslt : $rslt;
}
1;