iosswiftreactive-cocoa

Getting "use of undeclared type 'NoError'" with ReactiveCocoa

I am trying to learn ReactiveCocoa and have a hard time getting started. I keep hitting minor bumps as API and tutorials seems to be outdated quickly. Maybe I have the wrong impression.

Just trying to follow this I do not seem to have NoError.

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It should be imported correctly, since I have access to Signal, rac_textSignal etc. but I don't know why NoError is not available.

Their documentation mentions NoError as well but that leads to a 404.

This transition to RAC4 mentions NoError as well. Why is NoError undeclared? I am using ReactiveCocoa 4.0.1.

Edit: I just added public enum NoError : ErrorType {} to the top of the file and it works now. I am not sure if this is a proper solution to the problem though. It is not mentioned in guides and tutorials that I should extend ErrorType myself.

Solution

  • The reactive cocoa native NoError was removed in 4.0.1 in favour of antitypicals implementation in Result (adds NoError to Result, see this). See e.g. issue #2704

    We can see this explicitly used in the source files, e.g.

    Hence, you probably need to include (antitypicals) Result whenever you intend to use NoError. One suggested fix in the issue thread is

    public typealias NoError = Result.NoError