tree-sitter/src/compiler/build_tables/item_set_closure.cc
Max Brunsfeld 0d763d229d cpplint
2014-04-28 21:46:43 -07:00

37 lines
1.4 KiB
C++

#include "compiler/build_tables/item_set_closure.h"
#include <set>
#include <vector>
#include "tree_sitter/compiler.h"
#include "compiler/build_tables/follow_sets.h"
#include "compiler/build_tables/item.h"
#include "compiler/prepared_grammar.h"
namespace tree_sitter {
using std::set;
using rules::Symbol;
using std::vector;
namespace build_tables {
const ParseItemSet item_set_closure(const ParseItem &item,
const PreparedGrammar &grammar) {
ParseItemSet result;
vector<ParseItem> items_to_add = { item };
while (!items_to_add.empty()) {
ParseItem item = items_to_add.back();
items_to_add.pop_back();
auto insertion_result = result.insert(item);
if (insertion_result.second) {
for (const auto &pair : follow_sets(item, grammar)) {
const Symbol &non_terminal = pair.first;
const set<Symbol> &terminals = pair.second;
for (const auto &terminal : terminals) {
ParseItem next_item(non_terminal, grammar.rule(non_terminal), 0, terminal);
items_to_add.push_back(next_item);
}
}
}
}
return result;
}
}
}