/**
* Copyright (c) 2004,2005 UCLA Compilers Group.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* Neither UCLA nor the names of its contributors may be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**/
/*
* All files in the distribution of JTB, The Java Tree Builder are
* Copyright 1997, 1998, 1999 by the Purdue Research Foundation of Purdue
* University. All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that this entire copyright notice is duplicated in all
* such copies, and that any documentation, announcements, and
* other materials related to such distribution and use acknowledge
* that the software was developed at Purdue University, West Lafayette,
* Indiana by Kevin Tao and Jens Palsberg. No charge may be made
* for copies, derivations, or distributions of this material
* without the express written consent of the copyright holder.
* Neither the name of the University nor the name of the author
* may be used to endorse or promote products derived from this
* material without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR ANY PARTICULAR PURPOSE.
*/
package EDU.purdue.jtb.misc.toolkit;
import EDU.purdue.jtb.syntaxtree.*;
import EDU.purdue.jtb.visitor.DepthFirstVisitor;
import EDU.purdue.jtb.visitor.ExpansionUnitTypeCounter;
import EDU.purdue.jtb.misc.Errors;
import java.util.*;
/*
* Class SchemeSemanticChecker checks over a grammar to make sure it conforms
* to the following constraints imposed by the Scheme tree builder:
*
* -Choices (i.e. ( x | y )) may only occur at the top level of a production,
* between nonterminals.
* -Whatever goes within a list, optional list, or optional must be a
* single non-terminal.
*/
public class SchemeSemanticChecker extends DepthFirstVisitor {
private boolean errorReported = false; // Only report errors in a prod. once
private boolean topLevel = true;
private String curProd;
//
// f0 -> JavaCCOptions()
// f1 -> <PARSER_BEGIN_TK>
// f2 -> <LPAREN>
// f3 -> <IDENTIFIER>
// f4 -> <RPAREN>
// f5 -> CompilationUnit()
// f6 -> <PARSER_END_TK>
// f7 -> <LPAREN>
// f8 -> <IDENTIFIER>
// f9 -> <RPAREN>
// f10 -> ( Production() )*
// f11 -> <EOF>
//
public void visit(JavaCCInput n) {
n.f10.accept(this);
}
//
// f0 -> JavaCodeProduction()
// | RegularExprProduction()
// | BNFProduction()
// | TokenManagerDecls()
//
public void visit(Production n) {
n.f0.accept(this);
}
//
// f0 -> <JAVACODE_TK>
// f1 -> ResultType()
// f2 -> <IDENTIFIER>
// f3 -> FormalParameters()
// f4 -> Block()
//
public void visit(JavaCodeProduction n) {
// Don't visit
}
//
// f0 -> ResultType()
// f1 -> <IDENTIFIER>
// f2 -> FormalParameters()
// f3 -> <COLON>
// f4 -> Block()
// f5 -> <LBRACE>
// f6 -> ExpansionChoices()
// f7 -> <RBRACE>
//
public void visit(BNFProduction n) {
curProd = n.f1.tokenImage;
n.f6.accept(this);
errorReported = false;
}
//
// f0 -> [ LexicalStateList() ]
// f1 -> RegExprKind()
// f2 -> [ <LBRACKET> <IGNORE_CASE_TK> <RBRACKET> ]
// f3 -> <COLON>
// f4 -> <LBRACE>
// f5 -> RegExprSpec()
// f6 -> ( <BIT_OR> RegExprSpec() )*
// f7 -> <RBRACE>
//
public void visit(RegularExprProduction n) {
// Don't visit
}
//
// f0 -> <TOKEN_MGR_DECLS_TK>
// f1 -> <COLON>
// f2 -> ClassBodyDeclaration()
//
public void visit(TokenManagerDecls n) {
// Don't visit
}
//
// f0 -> Expansion()
// f1 -> ( <BIT_OR> Expansion() )*
//
public void visit(ExpansionChoices n) {
if ( n.f1.present() ) {
if ( !errorReported && !topLevel ) {
Errors.softErr("In " + curProd + "()--choices may occur " +
"only at the top level.");
errorReported = true;
}
else {
topLevel = false;
n.f0.accept(this);
n.f1.accept(this);
topLevel = true;
}
}
else {
n.f0.accept(this);
n.f1.accept(this);
}
}
//
// f0 -> ( ExpansionUnit() )*
//
public void visit(Expansion n) {
if ( !errorReported && !topLevel && n.f0.size() > 1 ) {
ExpansionUnitTypeCounter v = new ExpansionUnitTypeCounter();
n.accept(v);
if ( v.getNumNormals() > 1 ) {
Errors.softErr("In " + curProd + "()--only single " +
"nonterminals may appear below the top level.");
errorReported = true;
}
}
else
n.f0.accept(this);
}
//
// f0 -> LocalLookahead()
// | Block()
// | <LPAREN> ExpansionChoices() <RPAREN> [ <PLUS> | <STAR> | <HOOK> ]
// | <LBRACKET> ExpansionChoices() <RBRACKET>
// | [ PrimaryExpression() <ASSIGN> ] ExpansionUnitTerm()
//
public void visit(ExpansionUnit n) {
switch ( n.f0.which ) {
case 0: return;
case 1: return;
case 2: // fall through to 3
case 3:
if ( topLevel ) {
topLevel = false;
n.f0.accept(this);
topLevel = true;
}
else n.f0.accept(this);
case 4: return;
default:
Errors.hardErr("n.f0.which = " + String.valueOf(n.f0.which));
break;
}
}
//
// f0 -> <LOOKAHEAD_TK>
// f1 -> <LPAREN>
// f2 -> [ <INTEGER_LITERAL> ]
// f3 -> [ <COMMA> ]
// f4 -> ExpansionChoices()
// f5 -> [ <COMMA> ]
// f6 -> [ <LBRACE> Expression() <RBRACE> ]
// f7 -> <RPAREN>
//
public void visit(LocalLookahead n) {
// Don't visit
}
}