--Try this one SEQ SKIP SEQ --a comment this.is ? an.input this.is ! an.output --back to level 1 indentation ALT input ? again STOP -- this should be ignored boolean & input ? yet.again SKIP PROC now.it.gets.complicated () SKIP : PROC multiple (INT multiple, INT entries, INT may, INT cause, INT problems) SEQ --comment with loads of indentation --this one is sufficient also SEQ --theres a tab here SEQ SEQ -- a tab followed by spaces SEQ : --time to check continuation lines INT this.should.be.allowed = ( 4 + 2 ) : -- a comment is allowed here but not in the 2 lines above --we need a process here after a specification STOP