136 lines
1.6 KiB
Text
136 lines
1.6 KiB
Text
/*
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* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
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* See the copyright notice in the ACK home directory, in the file "Copyright".
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*
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* Author: Ceriel J.H. Jacobs
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*/
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/* S T A T E M E N T S */
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/* stripped down version from the one in the Modula-2 compiler */
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/* $Header$ */
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{
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#include "idf.h"
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#include "LLlex.h"
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static int loopcount;
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}
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statement :
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[
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/*
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* This part is not in the reference grammar. The reference grammar
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* states : assignment | ProcedureCall | ...
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* but this gives LL(1) conflicts
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*/
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designator
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[
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ActualParameters?
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[ BECOMES
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| '=' { error("':=' expected instead of '='");
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DOT = BECOMES;
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}
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]
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expression
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]
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/*
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* end of changed part
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*/
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IfStatement
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CaseStatement
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WHILE
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expression
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DO
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StatementSequence
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END
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REPEAT
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StatementSequence
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UNTIL
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expression
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{ loopcount++; }
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LOOP
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StatementSequence
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END
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{ loopcount--; }
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ForStatement
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WithStatement
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EXIT
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{ if (!loopcount) error("EXIT not in a LOOP"); }
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ReturnStatement
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/* empty */
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]
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;
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StatementSequence :
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statement
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[ %persistent
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';'
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statement
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]*
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;
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IfStatement :
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IF expression
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THEN StatementSequence
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[
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ELSIF expression
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THEN StatementSequence
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]*
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[
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ELSE StatementSequence
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]?
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END
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;
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CaseStatement :
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CASE expression
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OF case
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[
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'|' case
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]*
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[ ELSE StatementSequence
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]?
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END
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;
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case :
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[ CaseLabelList ':'
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StatementSequence
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]?
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;
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ForStatement :
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FOR IDENT BECOMES expression TO expression
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[
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BY ConstExpression
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]
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DO StatementSequence
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END
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;
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WithStatement :
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WITH designator DO StatementSequence
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END
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;
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ReturnStatement :
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RETURN
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[
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expression
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]
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;
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