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mirror of synced 2024-11-15 11:33:23 +01:00
ImHex/source/lang/parser.cpp

601 lines
24 KiB
C++

#include "lang/parser.hpp"
#include <optional>
#include <variant>
#define MATCHES(x) (begin() && x)
#define TO_NUMERIC_EXPRESSION(node) new ASTNodeNumericExpression((node), new ASTNodeIntegerLiteral({ Token::ValueType::Signed32Bit, s32(0) }), Token::Operator::Plus)
// Definition syntax:
// [A] : Either A or no token
// [A|B] : Either A, B or no token
// <A|B> : Either A or B
// <A...> : One or more of A
// A B C : Sequence of tokens A then B then C
// (parseXXXX) : Parsing handled by other function
namespace hex::lang {
/* Mathematical expressions */
// Identifier::<Identifier[::]...>
ASTNode* Parser::parseScopeResolution(std::vector<std::string> &path) {
if (peek(IDENTIFIER, -1))
path.push_back(getValue<std::string>(-1));
if (MATCHES(sequence(SEPARATOR_SCOPE_RESOLUTION))) {
if (MATCHES(sequence(IDENTIFIER)))
return this->parseScopeResolution(path);
else
throwParseError("expected member name", -1);
} else
return TO_NUMERIC_EXPRESSION(new ASTNodeScopeResolution(path));
}
// <Identifier[.]...>
ASTNode* Parser::parseRValue(std::vector<std::string> &path) {
if (peek(IDENTIFIER, -1))
path.push_back(getValue<std::string>(-1));
if (MATCHES(sequence(SEPARATOR_DOT))) {
if (MATCHES(sequence(IDENTIFIER)))
return this->parseRValue(path);
else
throwParseError("expected member name", -1);
} else
return TO_NUMERIC_EXPRESSION(new ASTNodeRValue(path));
}
// <Integer|((parseMathematicalExpression))>
ASTNode* Parser::parseFactor() {
if (MATCHES(sequence(INTEGER)))
return TO_NUMERIC_EXPRESSION(new ASTNodeIntegerLiteral(getValue<Token::IntegerLiteral>(-1)));
else if (MATCHES(sequence(SEPARATOR_ROUNDBRACKETOPEN))) {
auto node = this->parseMathematicalExpression();
if (!MATCHES(sequence(SEPARATOR_ROUNDBRACKETCLOSE)))
throwParseError("expected closing parenthesis");
return node;
} else if (MATCHES(sequence(IDENTIFIER, SEPARATOR_SCOPE_RESOLUTION))) {
std::vector<std::string> path;
this->m_curr--;
return this->parseScopeResolution(path);
}
else if (MATCHES(sequence(IDENTIFIER))) {
std::vector<std::string> path;
return this->parseRValue(path);
}
else
throwParseError("expected integer or parenthesis");
}
// (parseFactor) <*|/> (parseFactor)
ASTNode* Parser::parseMultiplicativeExpression() {
auto node = this->parseFactor();
while (MATCHES(variant(OPERATOR_STAR, OPERATOR_SLASH))) {
auto op = getValue<Token::Operator>(-1);
node = new ASTNodeNumericExpression(node, this->parseFactor(), op);
}
return node;
}
// (parseMultiplicativeExpression) <+|-> (parseMultiplicativeExpression)
ASTNode* Parser::parseAdditiveExpression() {
auto node = this->parseMultiplicativeExpression();
while (MATCHES(variant(OPERATOR_PLUS, OPERATOR_MINUS))) {
auto op = getValue<Token::Operator>(-1);
node = new ASTNodeNumericExpression(node, this->parseMultiplicativeExpression(), op);
}
return node;
}
// (parseAdditiveExpression) < >>|<< > (parseAdditiveExpression)
ASTNode* Parser::parseShiftExpression() {
auto node = this->parseAdditiveExpression();
while (MATCHES(variant(OPERATOR_SHIFTLEFT, OPERATOR_SHIFTRIGHT))) {
auto op = getValue<Token::Operator>(-1);
node = new ASTNodeNumericExpression(node, this->parseAdditiveExpression(), op);
}
return node;
}
// (parseAdditiveExpression) < >=|<=|>|< > (parseAdditiveExpression)
ASTNode* Parser::parseRelationExpression() {
auto node = this->parseShiftExpression();
while (MATCHES(sequence(OPERATOR_BOOLGREATERTHAN) || sequence(OPERATOR_BOOLLESSTHAN) || sequence(OPERATOR_BOOLGREATERTHANOREQUALS) || sequence(OPERATOR_BOOLLESSTHANOREQUALS))) {
auto op = getValue<Token::Operator>(-1);
node = new ASTNodeNumericExpression(node, this->parseShiftExpression(), op);
}
return node;
}
// (parseRelationExpression) <==|!=> (parseRelationExpression)
ASTNode* Parser::parseEqualityExpression() {
auto node = this->parseRelationExpression();
while (MATCHES(sequence(OPERATOR_BOOLEQUALS) || sequence(OPERATOR_BOOLNOTEQUALS))) {
auto op = getValue<Token::Operator>(-1);
node = new ASTNodeNumericExpression(node, this->parseRelationExpression(), op);
}
return node;
}
// (parseEqualityExpression) & (parseEqualityExpression)
ASTNode* Parser::parseBinaryAndExpression() {
auto node = this->parseEqualityExpression();
while (MATCHES(sequence(OPERATOR_BITAND))) {
node = new ASTNodeNumericExpression(node, this->parseEqualityExpression(), Token::Operator::BitAnd);
}
return node;
}
// (parseBinaryAndExpression) ^ (parseBinaryAndExpression)
ASTNode* Parser::parseBinaryXorExpression() {
auto node = this->parseBinaryAndExpression();
while (MATCHES(sequence(OPERATOR_BITXOR))) {
node = new ASTNodeNumericExpression(node, this->parseBinaryAndExpression(), Token::Operator::BitXor);
}
return node;
}
// (parseBinaryXorExpression) | (parseBinaryXorExpression)
ASTNode* Parser::parseBinaryOrExpression() {
auto node = this->parseBinaryXorExpression();
while (MATCHES(sequence(OPERATOR_BITOR))) {
node = new ASTNodeNumericExpression(node, this->parseBinaryXorExpression(), Token::Operator::BitOr);
}
return node;
}
// (parseBinaryOrExpression) && (parseBinaryOrExpression)
ASTNode* Parser::parseBooleanAnd() {
auto node = this->parseBinaryOrExpression();
while (MATCHES(sequence(OPERATOR_BOOLAND))) {
node = new ASTNodeNumericExpression(node, this->parseBinaryOrExpression(), Token::Operator::BitOr);
}
return node;
}
// (parseBooleanAnd) ^^ (parseBooleanAnd)
ASTNode* Parser::parseBooleanXor() {
auto node = this->parseBooleanAnd();
while (MATCHES(sequence(OPERATOR_BOOLXOR))) {
node = new ASTNodeNumericExpression(node, this->parseBooleanAnd(), Token::Operator::BitOr);
}
return node;
}
// (parseBooleanXor) || (parseBooleanXor)
ASTNode* Parser::parseBooleanOr() {
auto node = this->parseBooleanXor();
while (MATCHES(sequence(OPERATOR_BOOLOR))) {
node = new ASTNodeNumericExpression(node, this->parseBooleanXor(), Token::Operator::BitOr);
}
return node;
}
// (parseBinaryOrExpression)
ASTNode* Parser::parseMathematicalExpression() {
return this->parseBooleanOr();
}
/* Control flow */
// if ((parseMathematicalExpression)) { (parseMember) }
ASTNode* Parser::parseConditional() {
auto condition = parseMathematicalExpression();
std::vector<ASTNode*> trueBody, falseBody;
ScopeExit cleanup([&]{
delete condition;
for (auto &statement : trueBody)
delete statement;
for (auto &statement : falseBody)
delete statement;
});
if (MATCHES(sequence(SEPARATOR_ROUNDBRACKETCLOSE, SEPARATOR_CURLYBRACKETOPEN))) {
while (!MATCHES(sequence(SEPARATOR_CURLYBRACKETCLOSE))) {
trueBody.push_back(parseMember());
}
} else if (MATCHES(sequence(SEPARATOR_ROUNDBRACKETCLOSE))) {
trueBody.push_back(parseMember());
} else
throwParseError("expected body of conditional statement");
if (MATCHES(sequence(KEYWORD_ELSE, SEPARATOR_CURLYBRACKETOPEN))) {
while (!MATCHES(sequence(SEPARATOR_CURLYBRACKETCLOSE))) {
falseBody.push_back(parseMember());
}
} else if (MATCHES(sequence(KEYWORD_ELSE))) {
falseBody.push_back(parseMember());
}
cleanup.release();
return new ASTNodeConditionalStatement(condition, trueBody, falseBody);
}
/* Type declarations */
// [be|le] <Identifier|u8|u16|u32|u64|u128|s8|s16|s32|s64|s128|float|double>
ASTNode* Parser::parseType(s32 startIndex) {
std::optional<std::endian> endian;
if (peekOptional(KEYWORD_LE, 0))
endian = std::endian::little;
else if (peekOptional(KEYWORD_BE, 0))
endian = std::endian::big;
if (getType(startIndex) == Token::Type::Identifier) { // Custom type
if (!this->m_types.contains(getValue<std::string>(startIndex)))
throwParseError("failed to parse type");
return new ASTNodeTypeDecl({ }, this->m_types[getValue<std::string>(startIndex)]->clone(), endian);
}
else { // Builtin type
return new ASTNodeTypeDecl({ }, new ASTNodeBuiltinType(getValue<Token::ValueType>(startIndex)), endian);
}
}
// using Identifier = (parseType)
ASTNode* Parser::parseUsingDeclaration() {
auto *temporaryType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-1));
if (temporaryType == nullptr) throwParseError("invalid type used in variable declaration", -1);
SCOPE_EXIT( delete temporaryType; );
if (peekOptional(KEYWORD_BE) || peekOptional(KEYWORD_LE))
return new ASTNodeTypeDecl(getValue<std::string>(-4), temporaryType->getType()->clone(), temporaryType->getEndian());
else
return new ASTNodeTypeDecl(getValue<std::string>(-3), temporaryType->getType()->clone(), temporaryType->getEndian());
}
// padding[(parseMathematicalExpression)]
ASTNode* Parser::parsePadding() {
auto size = parseMathematicalExpression();
if (!MATCHES(sequence(SEPARATOR_SQUAREBRACKETCLOSE))) {
delete size;
throwParseError("expected closing ']' at end of array declaration", -1);
}
return new ASTNodeArrayVariableDecl({ }, new ASTNodeTypeDecl({ }, new ASTNodeBuiltinType(Token::ValueType::Padding)), size);;
}
// (parseType) Identifier
ASTNode* Parser::parseMemberVariable() {
auto temporaryType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-2));
if (temporaryType == nullptr) throwParseError("invalid type used in variable declaration", -1);
SCOPE_EXIT( delete temporaryType; );
return new ASTNodeVariableDecl(getValue<std::string>(-1), temporaryType->getType()->clone());
}
// (parseType) Identifier[(parseMathematicalExpression)]
ASTNode* Parser::parseMemberArrayVariable() {
auto temporaryType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-3));
if (temporaryType == nullptr) throwParseError("invalid type used in variable declaration", -1);
SCOPE_EXIT( delete temporaryType; );
auto name = getValue<std::string>(-2);
auto size = parseMathematicalExpression();
if (!MATCHES(sequence(SEPARATOR_SQUAREBRACKETCLOSE)))
throwParseError("expected closing ']' at end of array declaration", -1);
return new ASTNodeArrayVariableDecl(name, temporaryType->getType()->clone(), size);
}
// (parseType) *Identifier : (parseType)
ASTNode* Parser::parseMemberPointerVariable() {
auto name = getValue<std::string>(-2);
auto temporaryPointerType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-4));
if (temporaryPointerType == nullptr) throwParseError("invalid type used in variable declaration", -1);
SCOPE_EXIT( delete temporaryPointerType; );
if (!MATCHES((optional(KEYWORD_BE), optional(KEYWORD_LE)) && sequence(VALUETYPE_UNSIGNED)))
throwParseError("expected unsigned builtin type as size", -1);
auto temporarySizeType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-1));
if (temporarySizeType == nullptr) throwParseError("invalid type used for pointer size", -1);
SCOPE_EXIT( delete temporarySizeType; );
return new ASTNodePointerVariableDecl(name, temporaryPointerType->getType()->clone(), temporarySizeType->getType()->clone());
}
// [(parsePadding)|(parseMemberVariable)|(parseMemberArrayVariable)|(parseMemberPointerVariable)]
ASTNode* Parser::parseMember() {
ASTNode *member;
if (MATCHES(sequence(VALUETYPE_PADDING, SEPARATOR_SQUAREBRACKETOPEN)))
member = parsePadding();
else if (MATCHES((optional(KEYWORD_BE), optional(KEYWORD_LE)) && variant(IDENTIFIER, VALUETYPE_ANY) && sequence(IDENTIFIER, SEPARATOR_SQUAREBRACKETOPEN)))
member = parseMemberArrayVariable();
else if (MATCHES((optional(KEYWORD_BE), optional(KEYWORD_LE)) && variant(IDENTIFIER, VALUETYPE_ANY) && sequence(IDENTIFIER)))
member = parseMemberVariable();
else if (MATCHES((optional(KEYWORD_BE), optional(KEYWORD_LE)) && variant(IDENTIFIER, VALUETYPE_ANY) && sequence(OPERATOR_STAR, IDENTIFIER, OPERATOR_INHERIT)))
member = parseMemberPointerVariable();
else if (MATCHES(sequence(KEYWORD_IF, SEPARATOR_ROUNDBRACKETOPEN)))
return parseConditional();
else if (MATCHES(sequence(SEPARATOR_ENDOFPROGRAM)))
throwParseError("unexpected end of program", -2);
else
throwParseError("invalid struct member", 0);
if (!MATCHES(sequence(SEPARATOR_ENDOFEXPRESSION)))
throwParseError("missing ';' at end of expression", -1);
return member;
}
// struct Identifier { <(parseMember)...> }
ASTNode* Parser::parseStruct() {
const auto structNode = new ASTNodeStruct();
const auto &typeName = getValue<std::string>(-2);
ScopeExit structGuard([&]{ delete structNode; });
while (!MATCHES(sequence(SEPARATOR_CURLYBRACKETCLOSE))) {
structNode->addMember(parseMember());
}
structGuard.release();
return new ASTNodeTypeDecl(typeName, structNode);
}
// union Identifier { <(parseMember)...> }
ASTNode* Parser::parseUnion() {
const auto unionNode = new ASTNodeUnion();
const auto &typeName = getValue<std::string>(-2);
ScopeExit unionGuard([&]{ delete unionNode; });
while (!MATCHES(sequence(SEPARATOR_CURLYBRACKETCLOSE))) {
unionNode->addMember(parseMember());
}
unionGuard.release();
return new ASTNodeTypeDecl(typeName, unionNode);
}
// enum Identifier : (parseType) { <<Identifier|Identifier = (parseMathematicalExpression)[,]>...> }
ASTNode* Parser::parseEnum() {
std::string typeName;
if (peekOptional(KEYWORD_BE) || peekOptional(KEYWORD_LE))
typeName = getValue<std::string>(-5);
else
typeName = getValue<std::string>(-4);
auto temporaryTypeDecl = dynamic_cast<ASTNodeTypeDecl*>(parseType(-2));
if (temporaryTypeDecl == nullptr) throwParseError("failed to parse type", -2);
auto underlyingType = dynamic_cast<ASTNodeBuiltinType*>(temporaryTypeDecl->getType());
if (underlyingType == nullptr) throwParseError("underlying type is not a built-in type", -2);
const auto enumNode = new ASTNodeEnum(underlyingType);
ScopeExit enumGuard([&]{ delete enumNode; });
ASTNode *lastEntry = nullptr;
while (!MATCHES(sequence(SEPARATOR_CURLYBRACKETCLOSE))) {
if (MATCHES(sequence(IDENTIFIER, OPERATOR_ASSIGNMENT))) {
auto name = getValue<std::string>(-2);
enumNode->addEntry(name, parseMathematicalExpression());
}
else if (MATCHES(sequence(IDENTIFIER))) {
ASTNode *valueExpr;
auto name = getValue<std::string>(-1);
if (enumNode->getEntries().empty()) {
auto type = underlyingType->getType();
switch (type) {
case Token::ValueType::Signed8Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, s8(0) });
break;
case Token::ValueType::Unsigned8Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, u8(0) });
break;
case Token::ValueType::Signed16Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, s16(0) });
break;
case Token::ValueType::Unsigned16Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, u16(0) });
break;
case Token::ValueType::Signed32Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, s32(0) });
break;
case Token::ValueType::Unsigned32Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, u32(0) });
break;
case Token::ValueType::Signed64Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, s64(0) });
break;
case Token::ValueType::Unsigned64Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, u64(0) });
break;
case Token::ValueType::Signed128Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, s128(0) });
break;
case Token::ValueType::Unsigned128Bit:
valueExpr = new ASTNodeIntegerLiteral({ type, u128(0) });
break;
default:
throwParseError("invalid enum underlying type", -1);
}
lastEntry = valueExpr;
}
else
valueExpr = new ASTNodeNumericExpression(lastEntry, new ASTNodeIntegerLiteral({ Token::ValueType::Signed32Bit, s32(1) }), Token::Operator::Plus);
enumNode->addEntry(name, valueExpr);
}
else if (MATCHES(sequence(SEPARATOR_ENDOFPROGRAM)))
throwParseError("unexpected end of program", -2);
else
throwParseError("invalid union member", 0);
if (!MATCHES(sequence(SEPARATOR_COMMA))) {
if (MATCHES(sequence(SEPARATOR_CURLYBRACKETCLOSE)))
break;
else
throwParseError("missing ',' between enum entries", 0);
}
}
enumGuard.release();
return new ASTNodeTypeDecl(typeName, enumNode);
}
// bitfield Identifier { <Identifier : (parseMathematicalExpression)[;]...> }
ASTNode* Parser::parseBitfield() {
std::string typeName = getValue<std::string>(-2);
const auto bitfieldNode = new ASTNodeBitfield();
ScopeExit enumGuard([&]{ delete bitfieldNode; });
while (!MATCHES(sequence(SEPARATOR_CURLYBRACKETCLOSE))) {
if (MATCHES(sequence(IDENTIFIER, OPERATOR_INHERIT))) {
auto name = getValue<std::string>(-2);
bitfieldNode->addEntry(name, parseMathematicalExpression());
}
else if (MATCHES(sequence(SEPARATOR_ENDOFPROGRAM)))
throwParseError("unexpected end of program", -2);
else
throwParseError("invalid bitfield member", 0);
if (!MATCHES(sequence(SEPARATOR_ENDOFEXPRESSION))) {
throwParseError("missing ';' at end of expression", -1);
}
}
enumGuard.release();
return new ASTNodeTypeDecl(typeName, bitfieldNode);
}
// (parseType) Identifier @ Integer
ASTNode* Parser::parseVariablePlacement() {
auto temporaryType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-3));
if (temporaryType == nullptr) throwParseError("invalid type used in variable declaration", -1);
SCOPE_EXIT( delete temporaryType; );
return new ASTNodeVariableDecl(getValue<std::string>(-2), temporaryType->getType()->clone(), parseMathematicalExpression());
}
// (parseType) Identifier[(parseMathematicalExpression)] @ Integer
ASTNode* Parser::parseArrayVariablePlacement() {
auto temporaryType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-3));
if (temporaryType == nullptr) throwParseError("invalid type used in variable declaration", -1);
SCOPE_EXIT( delete temporaryType; );
auto name = getValue<std::string>(-2);
auto size = parseMathematicalExpression();
if (!MATCHES(sequence(SEPARATOR_SQUAREBRACKETCLOSE)))
throwParseError("expected closing ']' at end of array declaration", -1);
if (!MATCHES(sequence(OPERATOR_AT)))
throwParseError("expected placement instruction", -1);
return new ASTNodeArrayVariableDecl(name, temporaryType->getType()->clone(), size, parseMathematicalExpression());
}
// (parseType) *Identifier : (parseType) @ Integer
ASTNode* Parser::parsePointerVariablePlacement() {
auto name = getValue<std::string>(-2);
auto temporaryPointerType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-4));
if (temporaryPointerType == nullptr) throwParseError("invalid type used in variable declaration", -1);
SCOPE_EXIT( delete temporaryPointerType; );
if (!MATCHES((optional(KEYWORD_BE), optional(KEYWORD_LE)) && sequence(VALUETYPE_UNSIGNED)))
throwParseError("expected unsigned builtin type as size", -1);
auto temporaryPointerSizeType = dynamic_cast<ASTNodeTypeDecl *>(parseType(-1));
if (temporaryPointerSizeType == nullptr) throwParseError("invalid size type used in pointer declaration", -1);
SCOPE_EXIT( delete temporaryPointerSizeType; );
if (!MATCHES(sequence(OPERATOR_AT)))
throwParseError("expected placement instruction", -1);
return new ASTNodePointerVariableDecl(name, temporaryPointerType->getType()->clone(), temporaryPointerSizeType->getType()->clone(), parseMathematicalExpression());
}
/* Program */
// <(parseUsingDeclaration)|(parseVariablePlacement)|(parseStruct)>
ASTNode* Parser::parseStatement() {
ASTNode *statement;
if (MATCHES(sequence(KEYWORD_USING, IDENTIFIER, OPERATOR_ASSIGNMENT) && (optional(KEYWORD_BE), optional(KEYWORD_LE)) && variant(IDENTIFIER, VALUETYPE_ANY)))
statement = dynamic_cast<ASTNodeTypeDecl*>(parseUsingDeclaration());
else if (MATCHES((optional(KEYWORD_BE), optional(KEYWORD_LE)) && variant(IDENTIFIER, VALUETYPE_ANY) && sequence(IDENTIFIER, SEPARATOR_SQUAREBRACKETOPEN)))
statement = parseArrayVariablePlacement();
else if (MATCHES((optional(KEYWORD_BE), optional(KEYWORD_LE)) && variant(IDENTIFIER, VALUETYPE_ANY) && sequence(IDENTIFIER, OPERATOR_AT)))
statement = parseVariablePlacement();
else if (MATCHES((optional(KEYWORD_BE), optional(KEYWORD_LE)) && variant(IDENTIFIER, VALUETYPE_ANY) && sequence(OPERATOR_STAR, IDENTIFIER, OPERATOR_INHERIT)))
statement = parsePointerVariablePlacement();
else if (MATCHES(sequence(KEYWORD_STRUCT, IDENTIFIER, SEPARATOR_CURLYBRACKETOPEN)))
statement = parseStruct();
else if (MATCHES(sequence(KEYWORD_UNION, IDENTIFIER, SEPARATOR_CURLYBRACKETOPEN)))
statement = parseUnion();
else if (MATCHES(sequence(KEYWORD_ENUM, IDENTIFIER, OPERATOR_INHERIT) && (optional(KEYWORD_BE), optional(KEYWORD_LE)) && sequence(VALUETYPE_UNSIGNED, SEPARATOR_CURLYBRACKETOPEN)))
statement = parseEnum();
else if (MATCHES(sequence(KEYWORD_BITFIELD, IDENTIFIER, SEPARATOR_CURLYBRACKETOPEN)))
statement = parseBitfield();
else throwParseError("invalid sequence", 0);
if (!MATCHES(sequence(SEPARATOR_ENDOFEXPRESSION)))
throwParseError("missing ';' at end of expression", -1);
if (auto typeDecl = dynamic_cast<ASTNodeTypeDecl*>(statement); typeDecl != nullptr)
this->m_types.insert({ typeDecl->getName().data(), typeDecl });
return statement;
}
// <(parseStatement)...> EndOfProgram
std::optional<std::vector<ASTNode*>> Parser::parse(const std::vector<Token> &tokens) {
this->m_curr = tokens.begin();
this->m_types.clear();
try {
auto program = parseTillToken(SEPARATOR_ENDOFPROGRAM);
if (program.empty() || this->m_curr != tokens.end())
throwParseError("program is empty!", -1);
return program;
} catch (ParseError &e) {
this->m_error = e;
}
return { };
}
}