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Expr3.om |
PROCEDURE Factor(VAR at: Attribute) : BOOLEAN; (* Factor = "(" Expression ")" | ("+" | "-") Factor | Constant . *) VAR minus: BOOLEAN; BEGIN IF sy = lparenSY THEN GetSy; IF ~Expression(at) OR (sy # rparenSY) THEN RETURN FALSE END; GetSy; RETURN TRUE ELSIF (sy = plusSY) OR (sy = minusSY) THEN minus := sy = minusSY; GetSy; IF Factor(at) THEN IF minus THEN at := - at; END; RETURN TRUE ELSE RETURN FALSE END; ELSE RETURN Constant(at) END; END Factor; |
Copyright © 1999 Andreas Borchert, in HTML konvertiert am 29.06.1999 |