+
+ # We must handle commands which can cause skipping even while we
+ # are skipping, otherwise we will not process nested conditionals
+ # correctly.
+ /^\@ifset\s+([a-zA-Z0-9_-]+)/ and do {
+ push @endwstack, $endw;
+ push @skstack, $skipping;
+ $endw = "ifset";
+ $skipping = 1 unless exists $defs{$1};
+ next;
+ };
+
+ /^\@ifclear\s+([a-zA-Z0-9_-]+)/ and do {
+ push @endwstack, $endw;
+ push @skstack, $skipping;
+ $endw = "ifclear";
+ $skipping = 1 if exists $defs{$1};
+ next;
+ };
+
+ /^\@(ignore|menu)\b/ and do {
+ push @endwstack, $endw;
+ push @skstack, $skipping;
+ $endw = $1;
+ $skipping = 1;
+ next;
+ };
+