    def compileSignalHead(self, line):
        # Wait for signal head <head name> to [not] show <appearance name> [or ...]
        if logLevel > 2: print '  {} - {}'.format(self.threadName, line)
        pattern = re.compile('\s*Wait\s+for\s+signal\s+head\s+(.+\S)\s+to\s+(not\s)?show\s+(.+\S)')
        result = re.findall(pattern, line)