result and option #2
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| # Err("foo").match do | ||
| # ok { :foo } | ||
| # err { :bar } | ||
| # end # => :bar |
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- Love the doc tests
- I see Rust's match as requiring that all cases are handled (exhaustive pattern matching) and also to expose inner values.
Based on this example, it's unclear if it yields or gives the original value somehow. It's not quite and_then but that is what this reminds me of. Actually maybe it's closer to https://doc.rust-lang.org/std/result/enum.Result.html#method.map_or_else.
- Random unsolicited advice, this cheatsheet is really helpful https://upsuper.github.io/rust-cheatsheet/?dark,large
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Yeah I borrowed this from another random gem that had taken a stab at Rust style Results, and I don't love it. I'm going to work up a proper example with case and probably ditch this unless I can come up with a better reason to have it.
| # | ||
| # @example | ||
| # Ok("foo").expect!("foo") # => "foo" | ||
| # Err("foo").expect!("foo") # => raise Errgonomic::ExpectError, "foo" |
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It's unclear from this example that the original "foo" or the later "foo" is raised. Picking different values would help.
Also, rust has a lint against using foo and bar in examples for variables. One way around this is with theming. Like planet names or characters from a show you like etc.
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Oh, good one. Now I want a linter for that in Ruby! (Yo @h3h!)
| @@ -97,6 +150,10 @@ def expect!(msg) | |||
| end | |||
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| # Return the inner value of an Err, else raise an exception when Ok. | |||
| # | |||
| # @example | |||
| # Ok("foo").unwrap_err! # => raise Errgonomic::UnwrapError, "value is an Ok" | |||
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From interface design perspective with errors: I think that beyond knowing the value was "ok" in this scenario they would also want to know what it held. I.e. if it's surprising that it's Ok, the contents might yield some clues.
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Nice. I haven't used this in Rust yet so was a bit on autopilot in the implementation. That makes a lot of sense.
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I'm not 100% sure what methods hide the original error message in Rust, I think some do. In general though, I consider exceptions a time when I want maximum context as by definition: something I didn't expect is happening.
| # Ok("foo").match do | ||
| # ok { :ok } | ||
| # err { :err } | ||
| # end # => :ok |
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Do you support pattern matching? https://docs.ruby-lang.org/en/3.0/syntax/pattern_matching_rdoc.html Could you?
Okay fine, let's do this. Add yard-doctest and go to town making a take on Result and Option that feels like Ruby.
The first take was a lot smaller and more opinionated. The kind of thing I could easily and uncontroversially drop into a Rails project. This next take is… unapologetic in bringing my Rust reflexes into Ruby. But may not be something I want to use in Rails.
More thought will be required about how I want to use this, but it sure was fun to write, especially after finding yard-doctest.