tree-sitter/src/compiler/lex_table.cc

83 lines
2.4 KiB
C++

#include "compiler/lex_table.h"
#include "compiler/rules/symbol.h"
namespace tree_sitter {
using std::string;
using std::to_string;
using std::map;
using std::set;
using rules::Symbol;
using rules::CharacterSet;
LexAction::LexAction() :
type(LexActionTypeError),
symbol(Symbol(-1)),
state_index(-1) {}
LexAction::LexAction(LexActionType type, size_t state_index, Symbol symbol, int precedence) :
type(type),
symbol(symbol),
state_index(state_index),
precedence(precedence) {}
LexAction LexAction::Error() {
return LexAction(LexActionTypeError, -1, Symbol(-1), 0);
}
LexAction LexAction::Advance(size_t state_index) {
return LexAction(LexActionTypeAdvance, state_index, Symbol(-1), 0);
}
LexAction LexAction::Accept(Symbol symbol, int precedence) {
return LexAction(LexActionTypeAccept, -1, symbol, precedence);
}
bool LexAction::operator==(const LexAction &other) const {
return
(type == other.type) &&
(state_index == other.state_index) &&
(symbol == other.symbol);
}
std::ostream& operator<<(std::ostream &stream, const LexAction &action) {
switch (action.type) {
case LexActionTypeError:
return stream << string("#<error>");
case LexActionTypeAccept:
return stream << string("#<accept ") + to_string(action.symbol.index) + ">";
case LexActionTypeAdvance:
return stream << string("#<advance ") + to_string(action.state_index) + ">";
default:
return stream;
}
}
set<CharacterSet> LexState::expected_inputs() const {
set<CharacterSet> result;
for (auto &pair : actions)
result.insert(pair.first);
return result;
}
LexStateId LexTable::add_state() {
states.push_back(LexState());
return states.size() - 1;
}
LexState & LexTable::state(LexStateId id) {
if (id < 0)
return error_state;
else
return states[id];
}
void LexTable::add_action(LexStateId id, CharacterSet match, LexAction action) {
state(id).actions[match] = action;
}
void LexTable::add_default_action(LexStateId id, LexAction action) {
state(id).default_action = action;
}
const LexStateId LexTable::ERROR_STATE_ID = -1;
}