43 lines
707 B
C++
43 lines
707 B
C++
#pragma once
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#include <optional>
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#include <string>
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#include <unordered_map>
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#include <vector>
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namespace xlang {
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template <typename T>
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class Scope {
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std::vector<std::unordered_map<std::string, T>> stack;
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public:
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void enter() {
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stack.emplace_back();
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}
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void leave() {
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stack.pop_back();
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}
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void add(const std::string &name, T v) {
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stack.back().emplace(name, v);
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}
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std::optional<T> get(const std::string &name) {
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for (auto scope = stack.end() - 1;; scope--) {
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auto it = scope->find(name);
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if (it != scope->end()) {
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return it->second;
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}
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if (scope == stack.begin()) {
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break;
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}
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}
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return {};
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}
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};
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} // namespace xlang
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