/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/**
* ExprParser
* This class is used to parse XSL Expressions
* @see ExprLexer
**/
#ifndef MITREXSL_EXPRPARSER_H
#define MITREXSL_EXPRPARSER_H
#include "txCore.h"
#include "mozilla/UniquePtr.h"
#include "nsString.h"
class Expr;
class txExprLexer;
class FunctionCall;
class LocationStep;
class nsAtom;
class PredicateList;
class Token;
class txIParseContext;
class txNodeTest;
class txExprParser {
public:
static nsresult createExpr(
const nsAString& aExpression,
txIParseContext* aContext, Expr** aExpr) {
return createExprInternal(aExpression, 0, aContext, aExpr);
}
/**
* Creates an Attribute Value Template using the given value
*/
static nsresult createAVT(
const nsAString& aAttrValue,
txIParseContext* aContext, Expr** aResult);
protected:
static nsresult createExprInternal(
const nsAString& aExpression,
uint32_t aSubStringPos,
txIParseContext* aContext, Expr** aExpr);
/**
* Using nsAutoPtr& to optimize passing the ownership to the
* created binary expression objects.
*/
static nsresult createBinaryExpr(mozilla::UniquePtr<Expr>& left,
mozilla::UniquePtr<Expr>& right, Token* op,
Expr** aResult);
static nsresult createExpr(txExprLexer& lexer, txIParseContext* aContext,
Expr** aResult);
static nsresult createFilterOrStep(txExprLexer& lexer,
txIParseContext* aContext, Expr** aResult);
static nsresult createFunctionCall(txExprLexer& lexer,
txIParseContext* aContext, Expr** aResult);
static nsresult createLocationStep(txExprLexer& lexer,
txIParseContext* aContext, Expr** aResult);
static nsresult createNodeTypeTest(txExprLexer& lexer, txNodeTest** aResult);
static nsresult createPathExpr(txExprLexer& lexer, txIParseContext* aContext,
Expr** aResult);
static nsresult createUnionExpr(txExprLexer& lexer, txIParseContext* aContext,
Expr** aResult);
static bool isLocationStepToken(Token* aToken);
static short precedence(Token* aToken);
/**
* Resolve a QName, given the mContext parse context.
* Returns prefix and localName as well as namespace ID
*/
static nsresult resolveQName(
const nsAString& aQName, nsAtom** aPrefix,
txIParseContext* aContext, nsAtom** aLocalName,
int32_t& aNamespace,
bool aIsNameTest =
false);
/**
* Using the given lexer, parses the tokens if they represent a
* predicate list
* If an error occurs a non-zero String pointer will be returned
* containing the error message.
* @param predicateList, the PredicateList to add predicate expressions to
* @param lexer the ExprLexer to use for parsing tokens
* @return 0 if successful, or a String pointer to the error message
*/
static nsresult parsePredicates(PredicateList* aPredicateList,
txExprLexer& lexer,
txIParseContext* aContext);
static nsresult parseParameters(FunctionCall* aFnCall, txExprLexer& lexer,
txIParseContext* aContext);
};
#endif
