746 lines
18 KiB
C++
746 lines
18 KiB
C++
// Copyright 2013 Dolphin Emulator Project
|
|
// Licensed under GPLv2+
|
|
// Refer to the license.txt file included.
|
|
|
|
#include <cassert>
|
|
#include <cmath>
|
|
#include <iostream>
|
|
#include <memory>
|
|
#include <regex>
|
|
#include <string>
|
|
#include <utility>
|
|
#include <vector>
|
|
|
|
#include "Common/Common.h"
|
|
#include "Common/StringUtil.h"
|
|
|
|
#include "InputCommon/ControlReference/ExpressionParser.h"
|
|
#include "InputCommon/ControlReference/FunctionExpression.h"
|
|
|
|
namespace ciface::ExpressionParser
|
|
{
|
|
using namespace ciface::Core;
|
|
|
|
Token::Token(TokenType type_) : type(type_)
|
|
{
|
|
}
|
|
|
|
Token::Token(TokenType type_, std::string data_) : type(type_), data(std::move(data_))
|
|
{
|
|
}
|
|
|
|
bool Token::IsBinaryOperator() const
|
|
{
|
|
return type >= TOK_BINARY_OPS_BEGIN && type < TOK_BINARY_OPS_END;
|
|
}
|
|
|
|
Lexer::Lexer(std::string expr_) : expr(std::move(expr_))
|
|
{
|
|
it = expr.begin();
|
|
}
|
|
|
|
std::string Lexer::FetchDelimString(char delim)
|
|
{
|
|
const std::string result = FetchCharsWhile([delim](char c) { return c != delim; });
|
|
if (it != expr.end())
|
|
++it;
|
|
return result;
|
|
}
|
|
|
|
std::string Lexer::FetchWordChars()
|
|
{
|
|
// Valid word characters:
|
|
std::regex rx(R"([a-z\d_])", std::regex_constants::icase);
|
|
|
|
return FetchCharsWhile([&rx](char c) { return std::regex_match(std::string(1, c), rx); });
|
|
}
|
|
|
|
Token Lexer::GetDelimitedLiteral()
|
|
{
|
|
return Token(TOK_LITERAL, FetchDelimString('\''));
|
|
}
|
|
|
|
Token Lexer::GetVariable()
|
|
{
|
|
return Token(TOK_VARIABLE, FetchWordChars());
|
|
}
|
|
|
|
Token Lexer::GetFullyQualifiedControl()
|
|
{
|
|
return Token(TOK_CONTROL, FetchDelimString('`'));
|
|
}
|
|
|
|
Token Lexer::GetBareword(char first_char)
|
|
{
|
|
return Token(TOK_BAREWORD, first_char + FetchWordChars());
|
|
}
|
|
|
|
Token Lexer::GetRealLiteral(char first_char)
|
|
{
|
|
std::string value;
|
|
value += first_char;
|
|
value += FetchCharsWhile([](char c) { return isdigit(c, std::locale::classic()) || ('.' == c); });
|
|
|
|
if (std::regex_match(value, std::regex(R"(\d+(\.\d+)?)")))
|
|
return Token(TOK_LITERAL, value);
|
|
|
|
return Token(TOK_INVALID);
|
|
}
|
|
|
|
Token Lexer::PeekToken()
|
|
{
|
|
const auto old_it = it;
|
|
const auto tok = NextToken();
|
|
it = old_it;
|
|
return tok;
|
|
}
|
|
|
|
Token Lexer::NextToken()
|
|
{
|
|
if (it == expr.end())
|
|
return Token(TOK_EOF);
|
|
|
|
char c = *it++;
|
|
switch (c)
|
|
{
|
|
case ' ':
|
|
case '\t':
|
|
case '\n':
|
|
case '\r':
|
|
return Token(TOK_WHITESPACE);
|
|
case '(':
|
|
return Token(TOK_LPAREN);
|
|
case ')':
|
|
return Token(TOK_RPAREN);
|
|
case '&':
|
|
return Token(TOK_AND);
|
|
case '|':
|
|
return Token(TOK_OR);
|
|
case '!':
|
|
return Token(TOK_NOT);
|
|
case '+':
|
|
return Token(TOK_ADD);
|
|
case '-':
|
|
return Token(TOK_SUB);
|
|
case '*':
|
|
return Token(TOK_MUL);
|
|
case '/':
|
|
return Token(TOK_DIV);
|
|
case '%':
|
|
return Token(TOK_MOD);
|
|
case '=':
|
|
return Token(TOK_ASSIGN);
|
|
case '<':
|
|
return Token(TOK_LTHAN);
|
|
case '>':
|
|
return Token(TOK_GTHAN);
|
|
case ',':
|
|
return Token(TOK_COMMA);
|
|
case '^':
|
|
return Token(TOK_XOR);
|
|
case '\'':
|
|
return GetDelimitedLiteral();
|
|
case '$':
|
|
return GetVariable();
|
|
case '`':
|
|
return GetFullyQualifiedControl();
|
|
default:
|
|
if (isalpha(c, std::locale::classic()))
|
|
return GetBareword(c);
|
|
else if (isdigit(c, std::locale::classic()))
|
|
return GetRealLiteral(c);
|
|
else
|
|
return Token(TOK_INVALID);
|
|
}
|
|
}
|
|
|
|
ParseStatus Lexer::Tokenize(std::vector<Token>& tokens)
|
|
{
|
|
while (true)
|
|
{
|
|
const std::size_t string_position = it - expr.begin();
|
|
Token tok = NextToken();
|
|
|
|
tok.string_position = string_position;
|
|
tok.string_length = it - expr.begin();
|
|
|
|
// Handle /* */ style comments.
|
|
if (tok.type == TOK_DIV && PeekToken().type == TOK_MUL)
|
|
{
|
|
const auto end_of_comment = expr.find("*/", it - expr.begin());
|
|
|
|
if (end_of_comment == std::string::npos)
|
|
return ParseStatus::SyntaxError;
|
|
|
|
tok.type = TOK_COMMENT;
|
|
tok.string_length = end_of_comment + 4;
|
|
|
|
it = expr.begin() + end_of_comment + 2;
|
|
}
|
|
|
|
tokens.push_back(tok);
|
|
|
|
if (tok.type == TOK_INVALID)
|
|
return ParseStatus::SyntaxError;
|
|
|
|
if (tok.type == TOK_EOF)
|
|
break;
|
|
}
|
|
return ParseStatus::Successful;
|
|
}
|
|
|
|
class ControlExpression : public Expression
|
|
{
|
|
public:
|
|
// Keep a shared_ptr to the device so the control pointer doesn't become invalid.
|
|
std::shared_ptr<Device> m_device;
|
|
|
|
explicit ControlExpression(ControlQualifier qualifier_) : qualifier(qualifier_) {}
|
|
ControlState GetValue() const override
|
|
{
|
|
if (!input)
|
|
return 0.0;
|
|
|
|
// Note: Inputs may return negative values in situations where opposing directions are
|
|
// activated. We clamp off the negative values here.
|
|
|
|
// FYI: Clamping values greater than 1.0 is purposely not done to support unbounded values in
|
|
// the future. (e.g. raw accelerometer/gyro data)
|
|
|
|
return std::max(0.0, input->GetState());
|
|
}
|
|
void SetValue(ControlState value) override
|
|
{
|
|
if (output)
|
|
output->SetState(value);
|
|
}
|
|
int CountNumControls() const override { return (input || output) ? 1 : 0; }
|
|
void UpdateReferences(ControlEnvironment& env) override
|
|
{
|
|
m_device = env.FindDevice(qualifier);
|
|
input = env.FindInput(qualifier);
|
|
output = env.FindOutput(qualifier);
|
|
}
|
|
|
|
private:
|
|
ControlQualifier qualifier;
|
|
Device::Input* input = nullptr;
|
|
Device::Output* output = nullptr;
|
|
};
|
|
|
|
class BinaryExpression : public Expression
|
|
{
|
|
public:
|
|
TokenType op;
|
|
std::unique_ptr<Expression> lhs;
|
|
std::unique_ptr<Expression> rhs;
|
|
|
|
BinaryExpression(TokenType op_, std::unique_ptr<Expression>&& lhs_,
|
|
std::unique_ptr<Expression>&& rhs_)
|
|
: op(op_), lhs(std::move(lhs_)), rhs(std::move(rhs_))
|
|
{
|
|
}
|
|
|
|
ControlState GetValue() const override
|
|
{
|
|
switch (op)
|
|
{
|
|
case TOK_AND:
|
|
return std::min(lhs->GetValue(), rhs->GetValue());
|
|
case TOK_OR:
|
|
return std::max(lhs->GetValue(), rhs->GetValue());
|
|
case TOK_ADD:
|
|
return lhs->GetValue() + rhs->GetValue();
|
|
case TOK_SUB:
|
|
return lhs->GetValue() - rhs->GetValue();
|
|
case TOK_MUL:
|
|
return lhs->GetValue() * rhs->GetValue();
|
|
case TOK_DIV:
|
|
{
|
|
const ControlState result = lhs->GetValue() / rhs->GetValue();
|
|
return std::isinf(result) ? 0.0 : result;
|
|
}
|
|
case TOK_MOD:
|
|
{
|
|
const ControlState result = std::fmod(lhs->GetValue(), rhs->GetValue());
|
|
return std::isnan(result) ? 0.0 : result;
|
|
}
|
|
case TOK_ASSIGN:
|
|
{
|
|
lhs->SetValue(rhs->GetValue());
|
|
return lhs->GetValue();
|
|
}
|
|
case TOK_LTHAN:
|
|
return lhs->GetValue() < rhs->GetValue();
|
|
case TOK_GTHAN:
|
|
return lhs->GetValue() > rhs->GetValue();
|
|
case TOK_COMMA:
|
|
{
|
|
// Eval and discard lhs:
|
|
lhs->GetValue();
|
|
return rhs->GetValue();
|
|
}
|
|
case TOK_XOR:
|
|
{
|
|
const auto lval = lhs->GetValue();
|
|
const auto rval = rhs->GetValue();
|
|
return std::max(std::min(1 - lval, rval), std::min(lval, 1 - rval));
|
|
}
|
|
default:
|
|
assert(false);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
void SetValue(ControlState value) override
|
|
{
|
|
// Don't do anything special with the op we have.
|
|
// Treat "A & B" the same as "A | B".
|
|
lhs->SetValue(value);
|
|
rhs->SetValue(value);
|
|
}
|
|
|
|
int CountNumControls() const override
|
|
{
|
|
return lhs->CountNumControls() + rhs->CountNumControls();
|
|
}
|
|
|
|
void UpdateReferences(ControlEnvironment& env) override
|
|
{
|
|
lhs->UpdateReferences(env);
|
|
rhs->UpdateReferences(env);
|
|
}
|
|
};
|
|
|
|
class LiteralExpression : public Expression
|
|
{
|
|
public:
|
|
void SetValue(ControlState) override
|
|
{
|
|
// Do nothing.
|
|
}
|
|
|
|
int CountNumControls() const override { return 1; }
|
|
|
|
void UpdateReferences(ControlEnvironment&) override
|
|
{
|
|
// Nothing needed.
|
|
}
|
|
|
|
protected:
|
|
virtual std::string GetName() const = 0;
|
|
};
|
|
|
|
class LiteralReal : public LiteralExpression
|
|
{
|
|
public:
|
|
LiteralReal(ControlState value) : m_value(value) {}
|
|
|
|
ControlState GetValue() const override { return m_value; }
|
|
|
|
std::string GetName() const override { return ValueToString(m_value); }
|
|
|
|
private:
|
|
const ControlState m_value{};
|
|
};
|
|
|
|
ParseResult MakeLiteralExpression(Token token)
|
|
{
|
|
ControlState val{};
|
|
if (TryParse(token.data, &val))
|
|
return ParseResult::MakeSuccessfulResult(std::make_unique<LiteralReal>(val));
|
|
else
|
|
return ParseResult::MakeErrorResult(token, _trans("Invalid literal."));
|
|
}
|
|
|
|
class VariableExpression : public Expression
|
|
{
|
|
public:
|
|
VariableExpression(std::string name) : m_name(name) {}
|
|
|
|
ControlState GetValue() const override { return *m_value_ptr; }
|
|
|
|
void SetValue(ControlState value) override { *m_value_ptr = value; }
|
|
|
|
int CountNumControls() const override { return 1; }
|
|
|
|
void UpdateReferences(ControlEnvironment& env) override
|
|
{
|
|
m_value_ptr = env.GetVariablePtr(m_name);
|
|
}
|
|
|
|
protected:
|
|
const std::string m_name;
|
|
ControlState* m_value_ptr{};
|
|
};
|
|
|
|
// This class proxies all methods to its either left-hand child if it has bound controls, or its
|
|
// right-hand child. Its intended use is for supporting old-style barewords expressions.
|
|
class CoalesceExpression : public Expression
|
|
{
|
|
public:
|
|
CoalesceExpression(std::unique_ptr<Expression>&& lhs, std::unique_ptr<Expression>&& rhs)
|
|
: m_lhs(std::move(lhs)), m_rhs(std::move(rhs))
|
|
{
|
|
}
|
|
|
|
ControlState GetValue() const override { return GetActiveChild()->GetValue(); }
|
|
void SetValue(ControlState value) override { GetActiveChild()->SetValue(value); }
|
|
|
|
int CountNumControls() const override { return GetActiveChild()->CountNumControls(); }
|
|
void UpdateReferences(ControlEnvironment& env) override
|
|
{
|
|
m_lhs->UpdateReferences(env);
|
|
m_rhs->UpdateReferences(env);
|
|
}
|
|
|
|
private:
|
|
const std::unique_ptr<Expression>& GetActiveChild() const
|
|
{
|
|
return m_lhs->CountNumControls() > 0 ? m_lhs : m_rhs;
|
|
}
|
|
|
|
std::unique_ptr<Expression> m_lhs;
|
|
std::unique_ptr<Expression> m_rhs;
|
|
};
|
|
|
|
std::shared_ptr<Device> ControlEnvironment::FindDevice(ControlQualifier qualifier) const
|
|
{
|
|
if (qualifier.has_device)
|
|
return container.FindDevice(qualifier.device_qualifier);
|
|
else
|
|
return container.FindDevice(default_device);
|
|
}
|
|
|
|
Device::Input* ControlEnvironment::FindInput(ControlQualifier qualifier) const
|
|
{
|
|
const std::shared_ptr<Device> device = FindDevice(qualifier);
|
|
if (!device)
|
|
return nullptr;
|
|
|
|
return device->FindInput(qualifier.control_name);
|
|
}
|
|
|
|
Device::Output* ControlEnvironment::FindOutput(ControlQualifier qualifier) const
|
|
{
|
|
const std::shared_ptr<Device> device = FindDevice(qualifier);
|
|
if (!device)
|
|
return nullptr;
|
|
|
|
return device->FindOutput(qualifier.control_name);
|
|
}
|
|
|
|
ControlState* ControlEnvironment::GetVariablePtr(const std::string& name)
|
|
{
|
|
return &m_variables[name];
|
|
}
|
|
|
|
ParseResult ParseResult::MakeEmptyResult()
|
|
{
|
|
ParseResult result;
|
|
result.status = ParseStatus::EmptyExpression;
|
|
return result;
|
|
}
|
|
|
|
ParseResult ParseResult::MakeSuccessfulResult(std::unique_ptr<Expression>&& expr)
|
|
{
|
|
ParseResult result;
|
|
result.status = ParseStatus::Successful;
|
|
result.expr = std::move(expr);
|
|
return result;
|
|
}
|
|
|
|
ParseResult ParseResult::MakeErrorResult(Token token, std::string description)
|
|
{
|
|
ParseResult result;
|
|
result.status = ParseStatus::SyntaxError;
|
|
result.token = std::move(token);
|
|
result.description = std::move(description);
|
|
return result;
|
|
}
|
|
|
|
class Parser
|
|
{
|
|
public:
|
|
explicit Parser(const std::vector<Token>& tokens_) : tokens(tokens_) { m_it = tokens.begin(); }
|
|
ParseResult Parse()
|
|
{
|
|
ParseResult result = ParseToplevel();
|
|
|
|
if (ParseStatus::Successful != result.status)
|
|
return result;
|
|
|
|
if (Peek().type == TOK_EOF)
|
|
return result;
|
|
|
|
return ParseResult::MakeErrorResult(Peek(), _trans("Expected end of expression."));
|
|
}
|
|
|
|
private:
|
|
const std::vector<Token>& tokens;
|
|
std::vector<Token>::const_iterator m_it;
|
|
|
|
Token Chew()
|
|
{
|
|
const Token tok = Peek();
|
|
if (TOK_EOF != tok.type)
|
|
++m_it;
|
|
return tok;
|
|
}
|
|
|
|
Token Peek() { return *m_it; }
|
|
|
|
bool Expects(TokenType type)
|
|
{
|
|
Token tok = Chew();
|
|
return tok.type == type;
|
|
}
|
|
|
|
ParseResult ParseFunctionArguments(const std::string_view& func_name,
|
|
std::unique_ptr<FunctionExpression>&& func,
|
|
const Token& func_tok)
|
|
{
|
|
std::vector<std::unique_ptr<Expression>> args;
|
|
|
|
if (TOK_LPAREN != Peek().type)
|
|
{
|
|
// Single argument with no parens (useful for unary ! function)
|
|
const auto tok = Chew();
|
|
auto arg = ParseAtom(tok);
|
|
if (ParseStatus::Successful != arg.status)
|
|
return arg;
|
|
|
|
args.emplace_back(std::move(arg.expr));
|
|
}
|
|
else
|
|
{
|
|
// Chew the L-Paren
|
|
Chew();
|
|
|
|
// Check for empty argument list:
|
|
if (TOK_RPAREN == Peek().type)
|
|
{
|
|
Chew();
|
|
}
|
|
else
|
|
{
|
|
while (true)
|
|
{
|
|
// Read one argument.
|
|
// Grab an expression, but stop at comma.
|
|
auto arg = ParseBinary(BinaryOperatorPrecedence(TOK_COMMA));
|
|
if (ParseStatus::Successful != arg.status)
|
|
return arg;
|
|
|
|
args.emplace_back(std::move(arg.expr));
|
|
|
|
// Right paren is the end of our arguments.
|
|
const Token tok = Chew();
|
|
if (TOK_RPAREN == tok.type)
|
|
break;
|
|
|
|
// Comma before the next argument.
|
|
if (TOK_COMMA != tok.type)
|
|
return ParseResult::MakeErrorResult(tok, _trans("Expected comma."));
|
|
};
|
|
}
|
|
}
|
|
|
|
const auto argument_validation = func->SetArguments(std::move(args));
|
|
|
|
if (std::holds_alternative<FunctionExpression::ExpectedArguments>(argument_validation))
|
|
{
|
|
const auto text = std::string(func_name) + '(' +
|
|
std::get<FunctionExpression::ExpectedArguments>(argument_validation).text +
|
|
')';
|
|
|
|
return ParseResult::MakeErrorResult(func_tok, _trans("Expected arguments: " + text));
|
|
}
|
|
|
|
return ParseResult::MakeSuccessfulResult(std::move(func));
|
|
}
|
|
|
|
ParseResult ParseAtom(const Token& tok)
|
|
{
|
|
switch (tok.type)
|
|
{
|
|
case TOK_BAREWORD:
|
|
{
|
|
auto func = MakeFunctionExpression(tok.data);
|
|
|
|
if (!func)
|
|
{
|
|
// Invalid function, interpret this as a bareword control.
|
|
Token control_tok(tok);
|
|
control_tok.type = TOK_CONTROL;
|
|
return ParseAtom(control_tok);
|
|
}
|
|
|
|
return ParseFunctionArguments(tok.data, std::move(func), tok);
|
|
}
|
|
case TOK_CONTROL:
|
|
{
|
|
ControlQualifier cq;
|
|
cq.FromString(tok.data);
|
|
return ParseResult::MakeSuccessfulResult(std::make_unique<ControlExpression>(cq));
|
|
}
|
|
case TOK_NOT:
|
|
{
|
|
return ParseFunctionArguments("not", MakeFunctionExpression("not"), tok);
|
|
}
|
|
case TOK_LITERAL:
|
|
{
|
|
return MakeLiteralExpression(tok);
|
|
}
|
|
case TOK_VARIABLE:
|
|
{
|
|
return ParseResult::MakeSuccessfulResult(std::make_unique<VariableExpression>(tok.data));
|
|
}
|
|
case TOK_LPAREN:
|
|
{
|
|
return ParseParens();
|
|
}
|
|
case TOK_SUB:
|
|
{
|
|
// An atom was expected but we got a subtraction symbol.
|
|
// Interpret it as a unary minus function.
|
|
return ParseFunctionArguments("minus", MakeFunctionExpression("minus"), tok);
|
|
}
|
|
default:
|
|
{
|
|
return ParseResult::MakeErrorResult(tok, _trans("Expected start of expression."));
|
|
}
|
|
}
|
|
}
|
|
|
|
static int BinaryOperatorPrecedence(TokenType type)
|
|
{
|
|
switch (type)
|
|
{
|
|
case TOK_MUL:
|
|
case TOK_DIV:
|
|
case TOK_MOD:
|
|
return 1;
|
|
case TOK_ADD:
|
|
case TOK_SUB:
|
|
return 2;
|
|
case TOK_GTHAN:
|
|
case TOK_LTHAN:
|
|
return 3;
|
|
case TOK_AND:
|
|
return 4;
|
|
case TOK_XOR:
|
|
return 5;
|
|
case TOK_OR:
|
|
return 6;
|
|
case TOK_ASSIGN:
|
|
return 7;
|
|
case TOK_COMMA:
|
|
return 8;
|
|
default:
|
|
assert(false);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
ParseResult ParseBinary(int precedence = 999)
|
|
{
|
|
ParseResult lhs = ParseAtom(Chew());
|
|
|
|
if (lhs.status == ParseStatus::SyntaxError)
|
|
return lhs;
|
|
|
|
std::unique_ptr<Expression> expr = std::move(lhs.expr);
|
|
|
|
// TODO: handle LTR/RTL associativity?
|
|
while (Peek().IsBinaryOperator() && BinaryOperatorPrecedence(Peek().type) < precedence)
|
|
{
|
|
const Token tok = Chew();
|
|
ParseResult rhs = ParseBinary(BinaryOperatorPrecedence(tok.type));
|
|
if (rhs.status == ParseStatus::SyntaxError)
|
|
{
|
|
return rhs;
|
|
}
|
|
|
|
expr = std::make_unique<BinaryExpression>(tok.type, std::move(expr), std::move(rhs.expr));
|
|
}
|
|
|
|
return ParseResult::MakeSuccessfulResult(std::move(expr));
|
|
}
|
|
|
|
ParseResult ParseParens()
|
|
{
|
|
// lparen already chewed
|
|
ParseResult result = ParseToplevel();
|
|
if (result.status != ParseStatus::Successful)
|
|
return result;
|
|
|
|
const auto rparen = Chew();
|
|
if (rparen.type != TOK_RPAREN)
|
|
{
|
|
return ParseResult::MakeErrorResult(rparen, _trans("Expected closing paren."));
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
ParseResult ParseToplevel() { return ParseBinary(); }
|
|
}; // namespace ExpressionParser
|
|
|
|
ParseResult ParseTokens(const std::vector<Token>& tokens)
|
|
{
|
|
return Parser(tokens).Parse();
|
|
}
|
|
|
|
static ParseResult ParseComplexExpression(const std::string& str)
|
|
{
|
|
Lexer l(str);
|
|
std::vector<Token> tokens;
|
|
const ParseStatus tokenize_status = l.Tokenize(tokens);
|
|
if (tokenize_status != ParseStatus::Successful)
|
|
return ParseResult::MakeErrorResult(Token(TOK_INVALID), _trans("Tokenizing failed."));
|
|
|
|
RemoveInertTokens(&tokens);
|
|
return ParseTokens(tokens);
|
|
}
|
|
|
|
void RemoveInertTokens(std::vector<Token>* tokens)
|
|
{
|
|
tokens->erase(std::remove_if(tokens->begin(), tokens->end(),
|
|
[](const Token& tok) {
|
|
return tok.type == TOK_COMMENT || tok.type == TOK_WHITESPACE;
|
|
}),
|
|
tokens->end());
|
|
}
|
|
|
|
static std::unique_ptr<Expression> ParseBarewordExpression(const std::string& str)
|
|
{
|
|
ControlQualifier qualifier;
|
|
qualifier.control_name = str;
|
|
qualifier.has_device = false;
|
|
|
|
return std::make_unique<ControlExpression>(qualifier);
|
|
}
|
|
|
|
ParseResult ParseExpression(const std::string& str)
|
|
{
|
|
if (StripSpaces(str).empty())
|
|
return ParseResult::MakeEmptyResult();
|
|
|
|
auto bareword_expr = ParseBarewordExpression(str);
|
|
ParseResult complex_result = ParseComplexExpression(str);
|
|
|
|
if (complex_result.status != ParseStatus::Successful)
|
|
{
|
|
// This is a bit odd.
|
|
// Return the error status of the complex expression with the fallback barewords expression.
|
|
complex_result.expr = std::move(bareword_expr);
|
|
return complex_result;
|
|
}
|
|
|
|
complex_result.expr = std::make_unique<CoalesceExpression>(std::move(bareword_expr),
|
|
std::move(complex_result.expr));
|
|
return complex_result;
|
|
}
|
|
} // namespace ciface::ExpressionParser
|