Class Macro

parser/macro.h:69–167

Macro interface for describing the function signature to match and the MacroExpander to apply. Note: when a Macro should apply to multiple overloads (based on arg count) of a given function, a Macro should be created per arg-count.

// Note: when a Macro should apply to multiple overloads (based on arg count) of
// a given function, a Macro should be created per arg-count.
class Macro final {
 public:
  static absl::StatusOr<Macro> Global(absl::string_view name,
                                      size_t argument_count,
                                      GlobalMacroExpander expander);

  static absl::StatusOr<Macro> GlobalVarArg(absl::string_view name,
                                            GlobalMacroExpander expander);

  static absl::StatusOr<Macro> Receiver(absl::string_view name,
                                        size_t argument_count,
                                        ReceiverMacroExpander expander);

  static absl::StatusOr<Macro> ReceiverVarArg(absl::string_view name,
                                              ReceiverMacroExpander expander);

  Macro(const Macro&) = default;
  Macro(Macro&&) = default;
  Macro& operator=(const Macro&) = default;
  Macro& operator=(Macro&&) = default;

  // Function name to match.
  absl::string_view function() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
    return rep_->function;
  }

  // argument_count() for the function call.
  //
  // When the macro is a var-arg style macro, the return value will be zero, but
  // the MacroKey will contain a `*` where the arg count would have been.
  size_t argument_count() const { return rep_->arg_count; }

  // is_receiver_style returns true if the macro matches a receiver style call.
  bool is_receiver_style() const { return rep_->receiver_style; }

  bool is_variadic() const { return rep_->var_arg_style; }

  // key() returns the macro signatures accepted by this macro.
  //
  // Format: `<function>:<arg-count>:<is-receiver>`.
  //
  // When the macros is a var-arg style macro, the `arg-count` value is
  // represented as a `*`.
  absl::string_view key() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
    return rep_->key;
  }

  // Expander returns the MacroExpander to apply when the macro key matches the
  // parsed call signature.
  const MacroExpander& expander() const ABSL_ATTRIBUTE_LIFETIME_BOUND {
    return rep_->expander;
  }

  ABSL_MUST_USE_RESULT absl::optional<Expr> Expand(
      MacroExprFactory& factory,
      absl::optional<std::reference_wrapper<Expr>> target,
      absl::Span<Expr> arguments) const {
    return (expander())(factory, target, arguments);