Removed unnecessary std::move, fixes #533

[liuzicheng1987]

No description provided.

[gemini-code-assist]

Summary of Changes

Hello @liuzicheng1987, I'm Gemini Code Assist¹! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request addresses an identified issue by removing an unnecessary std::move operation within the to_single_error_message function. The std::move was incorrectly applied to the result of _errors[0].what(), which yields a const char*. This change simplifies the code, improves clarity, and aligns with C++ best practices by avoiding std::move where it provides no semantic benefit and could potentially hinder compiler optimizations or create confusion.

Highlights

• Unnecessary std::move removal: The std::move call was removed from the return statement return std::move(_errors[0].what()); in the to_single_error_message function. This change was made because _errors[0].what() returns a const char*, making std::move ineffective and potentially misleading in this context, as const char* does not have move semantics.

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[gemini-code-assist]

Code Review

This pull request correctly removes an unnecessary std::move. While the change is correct, there's an opportunity to further improve performance by enabling move semantics to avoid a string copy. I've left a specific suggestion to illustrate this.

[gemini-code-assist]

You are correct that std::move was unnecessary on the result of what(), as _errors[0].what() resolves to the const & overload, returning a const std::string&. Moving from a const reference results in a copy.

However, since _errors is passed by value, we can move from its elements. By moving from the Error object itself, you can invoke the &&-qualified overload of what(), which moves the string instead of copying it. This is more efficient.

Suggested change

	return _errors[0].what();
	return std::move(_errors[0]).what();