From 82e04846db893385f8efad37b0a0e71732cfeab6 Mon Sep 17 00:00:00 2001
From: Jan Travnicek <Jan.Travnicek@fit.cvut.cz>
Date: Thu, 17 Jul 2014 22:21:14 +0200
Subject: [PATCH] GNF internal form
---
alib2data/src/grammar/ContextFree/GNF.cpp | 82 +++++++------------
alib2data/src/grammar/ContextFree/GNF.h | 11 ++-
.../src/grammar/GrammarFromXMLParser.cpp | 16 +++-
alib2data/src/grammar/GrammarFromXMLParser.h | 1 +
.../src/grammar/GrammarToXMLComposer.cpp | 15 +++-
alib2data/src/grammar/GrammarToXMLComposer.h | 1 +
alib2data/test-src/grammar/GrammarTest.cpp | 30 +++++++
7 files changed, 96 insertions(+), 60 deletions(-)
diff --git a/alib2data/src/grammar/ContextFree/GNF.cpp b/alib2data/src/grammar/ContextFree/GNF.cpp
index 45e460387f..4bf533992a 100644
--- a/alib2data/src/grammar/ContextFree/GNF.cpp
+++ b/alib2data/src/grammar/ContextFree/GNF.cpp
@@ -32,12 +32,9 @@ GrammarBase* GNF::plunder() && {
}
bool GNF::removeTerminalSymbol(const alphabet::Symbol& symbol) {
- for(const std::pair<alphabet::Symbol, std::set<std::vector<alphabet::Symbol>>>& rule : rules) {
- if(rule.first == symbol)
- throw GrammarException("Symbol \"" + (std::string) symbol.getSymbol() + "\" is used in rule.");
-
- for(const std::vector<alphabet::Symbol>& rhs : rule.second)
- if(std::find(rhs.begin(), rhs.end(), symbol) != rhs.end())
+ for(const std::pair<alphabet::Symbol, std::set<std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >> >& rule : rules) {
+ for(const std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >& rhs : rule.second)
+ if(rhs.first == symbol)
throw GrammarException("Symbol \"" + (std::string) symbol.getSymbol() + "\" is used in rule.");
}
@@ -45,12 +42,12 @@ bool GNF::removeTerminalSymbol(const alphabet::Symbol& symbol) {
}
bool GNF::removeNonterminalSymbol(const alphabet::Symbol& symbol) {
- for(const std::pair<alphabet::Symbol, std::set<std::vector<alphabet::Symbol>>>& rule : rules) {
+ for(const std::pair<alphabet::Symbol, std::set<std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >> >& rule : rules) {
if(rule.first == symbol)
throw GrammarException("Symbol \"" + (std::string) symbol.getSymbol() + "\" is used in rule.");
- for(const std::vector<alphabet::Symbol>& rhs : rule.second)
- if(std::find(rhs.begin(), rhs.end(), symbol) != rhs.end())
+ for(const std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >& rhs : rule.second)
+ if(std::find(rhs.second.begin(), rhs.second.end(), symbol) != rhs.second.end())
throw GrammarException("Symbol \"" + (std::string) symbol.getSymbol() + "\" is used in rule.");
}
@@ -61,59 +58,36 @@ bool GNF::removeNonterminalSymbol(const alphabet::Symbol& symbol) {
return nonterminalAlphabet.erase(symbol);
}
-bool GNF::addRule(const alphabet::Symbol& leftHandSide, const std::vector<alphabet::Symbol>& rightHandSide) {
- int rSize = rightHandSide.size();
-
- if(rSize == 0 && leftHandSide == initialSymbol) {
- for(const auto& rule : rules) {
- for(const auto& ruleRHS : rule.second) {
- if(any_of(ruleRHS.begin(), ruleRHS.end(), [&](const alphabet::Symbol& symbol) { return initialSymbol == symbol; })) {
- throw GrammarException("Initial symbol " + (std::string) initialSymbol + "used on right hand side of already existing rule");
- }
- }
- }
-
- generatesEpsilon = true;
- return rules[leftHandSide].insert(rightHandSide).second;
- } else if(rSize == 1) {
- if(!nonterminalAlphabet.count(leftHandSide))
- throw GrammarException("Rule must rewrite nonterminal symbol");
-
- if(!terminalAlphabet.count(rightHandSide[0]))
- throw GrammarException("Rule must rewrite to terminal symbol");
-
- return rules[leftHandSide].insert(rightHandSide).second;
- } else {
- if(!nonterminalAlphabet.count(leftHandSide))
- throw GrammarException("Rule must rewrite nonterminal symbol");
-
- if(!terminalAlphabet.count(rightHandSide[0]))
- throw GrammarException("First symbol of the rule must be a terminal symbol");
-
- for(std::vector<alphabet::Symbol>::const_iterator iter = rightHandSide.begin() + 1; iter != rightHandSide.end(); iter++) {
- if(nonterminalAlphabet.find(*iter) == nonterminalAlphabet.end())
- throw GrammarException("Symbol \"" + (std::string) iter->getSymbol() + "\" is not a nonterminal symbol");
- if(generatesEpsilon && *iter == initialSymbol)
- throw GrammarException("Initial symbol is already allowed to be rewritten to epsilon");
- }
-
- return rules[leftHandSide].insert(rightHandSide).second;
- }
+bool GNF::addRule(const alphabet::Symbol& leftHandSide, const std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >& rightHandSide) {
+ if(!nonterminalAlphabet.count(leftHandSide))
+ throw GrammarException("Rule must rewrite nonterminal symbol");
+
+ if(!terminalAlphabet.count(rightHandSide.first))
+ throw GrammarException("Rule must rewrite to terminal symbol");
+
+ for(const alphabet::Symbol& rhsNTs : rightHandSide.second)
+ if(nonterminalAlphabet.find(rhsNTs) == nonterminalAlphabet.end())
+ throw GrammarException("Symbol \"" + (std::string) rhsNTs.getSymbol() + "\" is not a nonterminal symbol");
+
+ return rules[leftHandSide].insert(rightHandSide).second;
}
-const std::map<alphabet::Symbol, std::set<std::vector<alphabet::Symbol>>> GNF::getRules() const {
+const std::map<alphabet::Symbol, std::set<std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >> > GNF::getRules() const {
return rules;
}
-bool GNF::removeRule(const alphabet::Symbol& leftHandSide, const std::vector<alphabet::Symbol>& rightHandSide) {
- int rSize = rightHandSide.size();
-
- if(leftHandSide == initialSymbol && rSize == 0) {
- generatesEpsilon = false;
- }
+bool GNF::removeRule(const alphabet::Symbol& leftHandSide, const std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >& rightHandSide) {
return rules[leftHandSide].erase(rightHandSide);
}
+void GNF::setGeneratesEpsilon(bool genEps) {
+ generatesEpsilon = genEps;
+}
+
+bool GNF::getGeneratesEpsilon() const {
+ return generatesEpsilon;
+}
+
bool GNF::operator==(const GrammarBase& other) const {
return other == *this;
}
diff --git a/alib2data/src/grammar/ContextFree/GNF.h b/alib2data/src/grammar/ContextFree/GNF.h
index c711939be7..b3341ec7be 100644
--- a/alib2data/src/grammar/ContextFree/GNF.h
+++ b/alib2data/src/grammar/ContextFree/GNF.h
@@ -19,7 +19,7 @@ namespace grammar {
* Context free grammar in greibach normal form. Type 2 in Chomsky hierarchy. Produces context free languages.
*/
class GNF : public std::element<GNF, GrammarBase>, public TerminalNonterminalAlphabetInitialSymbol {
- std::map<alphabet::Symbol, std::set<std::vector<alphabet::Symbol>>> rules;
+ std::map<alphabet::Symbol, std::set<std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >> > rules;
bool generatesEpsilon;
public:
GNF(const alphabet::Symbol& initialSymbol);
@@ -30,16 +30,19 @@ public:
virtual GrammarBase* plunder() &&;
- bool addRule(const alphabet::Symbol& leftHandSide, const std::vector<alphabet::Symbol>& rightHandSide);
+ bool addRule(const alphabet::Symbol& leftHandSide, const std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >& rightHandSide);
- const std::map<alphabet::Symbol, std::set<std::vector<alphabet::Symbol>>> getRules() const;
+ const std::map<alphabet::Symbol, std::set<std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >> > getRules() const;
- bool removeRule(const alphabet::Symbol& leftHandSide, const std::vector<alphabet::Symbol>& rightHandSide);
+ bool removeRule(const alphabet::Symbol& leftHandSide, const std::pair<alphabet::Symbol, std::vector<alphabet::Symbol> >& rightHandSide);
bool removeTerminalSymbol(const alphabet::Symbol& symbol);
bool removeNonterminalSymbol(const alphabet::Symbol& symbol);
+ void setGeneratesEpsilon(bool genEps);
+ bool getGeneratesEpsilon() const;
+
virtual bool operator==(const GrammarBase& other) const;
virtual bool operator==(const GNF& other) const;
diff --git a/alib2data/src/grammar/GrammarFromXMLParser.cpp b/alib2data/src/grammar/GrammarFromXMLParser.cpp
index 75994a8499..9e60ddbda2 100644
--- a/alib2data/src/grammar/GrammarFromXMLParser.cpp
+++ b/alib2data/src/grammar/GrammarFromXMLParser.cpp
@@ -177,6 +177,9 @@ GNF GrammarFromXMLParser::parseGNF(std::list<sax::Token>& input) const {
parseRules(input, grammar);
+ bool generatesEpsilon = parseGeneratesEpsilon(input);
+ grammar.setGeneratesEpsilon(generatesEpsilon);
+
popToken(input, sax::Token::TokenType::END_ELEMENT, "GNF");
return grammar;
}
@@ -426,7 +429,7 @@ void GrammarFromXMLParser::parseRule(std::list<sax::Token>& input, CSG& grammar)
void GrammarFromXMLParser::parseRule(std::list<sax::Token>& input, GNF& grammar) const {
alphabet::Symbol lhs = parseRuleSingleSymbolLHS(input);
- std::vector<alphabet::Symbol> rhs = parseRuleRHS(input);
+ std::pair<alphabet::Symbol, std::vector<alphabet::Symbol>> rhs = parseRuleGNFRHS(input);
grammar.addRule(lhs, rhs);
}
@@ -499,6 +502,17 @@ alphabet::Symbol GrammarFromXMLParser::parseRuleSingleSymbolLHS(std::list<sax::T
return lhs;
}
+std::pair<alphabet::Symbol, std::vector<alphabet::Symbol>> GrammarFromXMLParser::parseRuleGNFRHS(std::list<sax::Token>& input) const {
+ popToken(input, sax::Token::TokenType::START_ELEMENT, "rhs");
+ alphabet::Symbol first = alib::FromXMLParsers::symbolParser.parse(input);
+ std::vector<alphabet::Symbol> second;
+ while (isTokenType(input, sax::Token::TokenType::START_ELEMENT)) {
+ second.push_back(alib::FromXMLParsers::symbolParser.parse(input));
+ }
+ popToken(input, sax::Token::TokenType::END_ELEMENT, "rhs");
+ return std::make_pair(first, second);
+}
+
std::vector<alphabet::Symbol> GrammarFromXMLParser::parseRuleRHS(std::list<sax::Token>& input) const {
std::vector<alphabet::Symbol> rhs;
popToken(input, sax::Token::TokenType::START_ELEMENT, "rhs");
diff --git a/alib2data/src/grammar/GrammarFromXMLParser.h b/alib2data/src/grammar/GrammarFromXMLParser.h
index fe4c8efbaa..ca218f90dc 100644
--- a/alib2data/src/grammar/GrammarFromXMLParser.h
+++ b/alib2data/src/grammar/GrammarFromXMLParser.h
@@ -45,6 +45,7 @@ protected:
std::vector<alphabet::Symbol> parseRuleLHS(std::list<sax::Token>& input) const;
alphabet::Symbol parseRuleSingleSymbolLHS(std::list<sax::Token>& input) const;
+ std::pair<alphabet::Symbol, std::vector<alphabet::Symbol>> parseRuleGNFRHS(std::list<sax::Token>& input) const;
std::vector<alphabet::Symbol> parseRuleRHS(std::list<sax::Token>& input) const;
std::variant<alphabet::Symbol, std::pair<alphabet::Symbol, alphabet::Symbol>> parseRuleOneOrTwoSymbolsRHS(std::list<sax::Token>& input) const;
diff --git a/alib2data/src/grammar/GrammarToXMLComposer.cpp b/alib2data/src/grammar/GrammarToXMLComposer.cpp
index 3ea70b05e0..2939f67ead 100644
--- a/alib2data/src/grammar/GrammarToXMLComposer.cpp
+++ b/alib2data/src/grammar/GrammarToXMLComposer.cpp
@@ -154,6 +154,7 @@ std::list<sax::Token> GrammarToXMLComposer::compose(const GNF& grammar) const {
composeTerminalAlphabet(out, grammar.getTerminalAlphabet());
composeInitialSymbol(out, grammar.getInitialSymbol());
composeRules(out, grammar);
+ composeGeneratesEpsilon(out, grammar.getGeneratesEpsilon());
out.push_back(sax::Token("GNF", sax::Token::TokenType::END_ELEMENT));
return out;
@@ -339,7 +340,7 @@ void GrammarToXMLComposer::composeRules(std::list<sax::Token>& out, const GNF& g
out.push_back(sax::Token("rule", sax::Token::TokenType::START_ELEMENT));
composeRuleSingleSymbolLHS(out, rule.first);
- composeRuleRHS(out, rhs);
+ composeRuleGNFRHS(out, rhs);
out.push_back(sax::Token("rule", sax::Token::TokenType::END_ELEMENT));
}
@@ -518,6 +519,18 @@ void GrammarToXMLComposer::composeRuleOneOrTwoSymbolsRHS(std::list<sax::Token>&
out.push_back(sax::Token("rhs", sax::Token::TokenType::END_ELEMENT));
}
+void GrammarToXMLComposer::composeRuleGNFRHS(std::list<sax::Token>& out, const std::pair<alphabet::Symbol, std::vector<alphabet::Symbol>>& symbols) const {
+ out.push_back(sax::Token("rhs", sax::Token::TokenType::START_ELEMENT));
+
+ out.splice(out.end(), alib::ToXMLComposers::symbolComposer.compose(symbols.first));
+
+ for (const auto& symbol : symbols.second) {
+ out.splice(out.end(), alib::ToXMLComposers::symbolComposer.compose(symbol));
+ }
+
+ out.push_back(sax::Token("rhs", sax::Token::TokenType::END_ELEMENT));
+}
+
void GrammarToXMLComposer::composeRuleLGRHS(std::list<sax::Token>& out, const std::variant<std::vector<alphabet::Symbol>, std::tuple<std::vector<alphabet::Symbol>, alphabet::Symbol, std::vector<alphabet::Symbol>>>& symbols) const {
out.push_back(sax::Token("rhs", sax::Token::TokenType::START_ELEMENT));
if(symbols.is<std::vector<alphabet::Symbol>>()) {
diff --git a/alib2data/src/grammar/GrammarToXMLComposer.h b/alib2data/src/grammar/GrammarToXMLComposer.h
index 0e8923f6b1..427eb2b92d 100644
--- a/alib2data/src/grammar/GrammarToXMLComposer.h
+++ b/alib2data/src/grammar/GrammarToXMLComposer.h
@@ -73,6 +73,7 @@ class GrammarToXMLComposer : public GrammarBase::const_visitor_type {
void composeRuleSingleSymbolLHS(std::list<sax::Token>& out, const alphabet::Symbol& symbol) const;
void composeRuleRHS(std::list<sax::Token>& out, const std::vector<alphabet::Symbol>& symbols) const;
void composeRuleOneOrTwoSymbolsRHS(std::list<sax::Token>& out, const std::variant<alphabet::Symbol, std::pair<alphabet::Symbol, alphabet::Symbol>>& symbols) const;
+ void composeRuleGNFRHS(std::list<sax::Token>& out, const std::pair<alphabet::Symbol, std::vector<alphabet::Symbol>>& symbols) const;
void composeRuleLeftLGRHS(std::list<sax::Token>& out, const std::variant<std::vector<alphabet::Symbol>, std::pair<alphabet::Symbol, std::vector<alphabet::Symbol>>>& symbols) const;
void composeRuleRightLGRHS(std::list<sax::Token>& out, const std::variant<std::vector<alphabet::Symbol>, std::pair<std::vector<alphabet::Symbol>, alphabet::Symbol>>& symbols) const;
void composeRuleLGRHS(std::list<sax::Token>& out, const std::variant<std::vector<alphabet::Symbol>, std::tuple<std::vector<alphabet::Symbol>, alphabet::Symbol, std::vector<alphabet::Symbol>>>& symbols) const;
diff --git a/alib2data/test-src/grammar/GrammarTest.cpp b/alib2data/test-src/grammar/GrammarTest.cpp
index ab2c4c8a09..d365f883c5 100644
--- a/alib2data/test-src/grammar/GrammarTest.cpp
+++ b/alib2data/test-src/grammar/GrammarTest.cpp
@@ -260,6 +260,36 @@ void GrammarTest::testContextFreeParser() {
grammar::GrammarFromXMLParser parser;
grammar::CNF grammar2 = parser.parseCNF(tokens2);
+ CPPUNIT_ASSERT( grammar == grammar2 );
+ }
+ }
+ {
+ grammar::GNF grammar(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(1)))));
+
+ grammar.addNonterminalSymbol(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(1)))));
+ grammar.addNonterminalSymbol(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(2)))));
+ grammar.addNonterminalSymbol(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(3)))));
+ grammar.addTerminalSymbol(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::StringLabel("a")))));
+ grammar.addTerminalSymbol(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::StringLabel("b")))));
+ grammar.setGeneratesEpsilon(true);
+
+ grammar.addRule(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(1)))), std::make_pair(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::StringLabel("a")))), std::vector<alphabet::Symbol> {alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(2))))}));
+ grammar.addRule(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(2)))), std::make_pair(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::StringLabel("b")))), std::vector<alphabet::Symbol> {alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(3))))}));
+ grammar.addRule(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(3)))), std::make_pair(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::StringLabel("a")))), std::vector<alphabet::Symbol> {}));
+ grammar.addRule(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::IntegerLabel(1)))), std::make_pair(alphabet::Symbol(alphabet::LabeledSymbol(label::Label(label::StringLabel("a")))), std::vector<alphabet::Symbol> {}));
+
+ CPPUNIT_ASSERT( grammar == grammar );
+ {
+ grammar::GrammarToXMLComposer composer;
+ std::list<sax::Token> tokens = composer.compose(grammar);
+ std::string tmp;
+ sax::SaxComposeInterface::printMemory(tmp, tokens);
+
+ std::list<sax::Token> tokens2;
+ sax::SaxParseInterface::parseMemory(tmp, tokens2);
+ grammar::GrammarFromXMLParser parser;
+ grammar::GNF grammar2 = parser.parseGNF(tokens2);
+
CPPUNIT_ASSERT( grammar == grammar2 );
}
}
--
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