Error should impl PartialEq

[yjhmelody]

I find now Error is bad to be compared.

Error cannot impl PartialEq beacuse of ExternalError, I think ExternalError should not be a dyn error.

And some error enum like FromLuaConversionError:

    /// A Lua value could not be converted to the expected Rust type.
    FromLuaConversionError {
        /// Name of the Lua type that could not be converted.
        from: &'static str,
        /// Name of the Rust type that could not be created.
        to: &'static str,
        /// A string containing more detailed error information.
        message: Option<StdString>,
    },

should have their own struct.

[jugglerchris]

Hi,
What's your use case for the error implementing PartialEq? This isn't the norm - e.g. std::io::Error doesn't.
Thanks!

[yjhmelody]

io::Error's error message are more dynamic. But most of rlua Error are static.

[jugglerchris]

But ExternalError is a feature - it means that Rust callbacks can return their own error type, which will be propagated through Lua - it's a feature. I think this is more useful than comparing errors for equality; I'm afraid I don't see a compelling reason to try to change this.

[SoniEx2]

Lua errors can be completely arbitrary, including error({}), error(function() end), error(nil), error(coroutine.create(function() end)), etc.

[jugglerchris]

@SoniEx2 In this case we're talking about the Rust-side Error enum, which only has Rust types.

[jugglerchris]

Closing as this is as designed.