src/tint/utils/macros/defer.h

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#ifndef SRC_TINT_UTILS_MACROS_DEFER_H_
#define SRC_TINT_UTILS_MACROS_DEFER_H_

#include <utility>

#include "src/tint/utils/macros/concat.h"

namespace tint {

/// Defer executes a function or function like object when it is destructed.
template <typename F>
class Defer {
  public:
    /// Constructor
    /// @param f the function to call when the Defer is destructed
    explicit Defer(F&& f) : f_(std::move(f)) {}

    /// Move constructor
    Defer(Defer&&) = default;

    /// Destructor
    /// Calls the deferred function
    ~Defer() { f_(); }

  private:
    Defer(const Defer&) = delete;
    Defer& operator=(const Defer&) = delete;

    F f_;
};

/// Constructor
/// @param f the function to call when the Defer is destructed
/// @return the defer object
template <typename F>
inline Defer<F> MakeDefer(F&& f) {
    return Defer<F>(std::forward<F>(f));
}

}  // namespace tint

/// TINT_DEFER(S) executes the statement(s) `S` when exiting the current lexical
/// scope.
#define TINT_DEFER(S) auto TINT_CONCAT(tint_defer_, __COUNTER__) = ::tint::MakeDefer([&] { S; })

#endif  // SRC_TINT_UTILS_MACROS_DEFER_H_