Class MutableListValue

common/values/list_value_builder.h:62–72

Extension of ParsedListValueInterface which is also mutable. Accessing this like a normal list before all elements are finished being appended is a bug. This is primarily used by the runtime to efficiently implement comprehensions which accumulate results into a list. IMPORTANT: This type is only meant to be utilized by the runtime.

//
// IMPORTANT: This type is only meant to be utilized by the runtime.
class MutableListValue : public CustomListValueInterface {
 public:
  virtual absl::Status Append(Value value) const = 0;

  virtual void Reserve(size_t capacity) const {}

 private:
  NativeTypeId GetNativeTypeId() const override {
    return NativeTypeId::For<MutableListValue>();
  }
};

// Special implementation of list which is both a modern list, legacy list, and
// mutable.