testable for seq and contramap (for testable)#412
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| (** [neg t] is [t]'s negation: it is [true] when [t] is [false] and it is | ||
| [false] when [t] is [true]. *) | ||
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| val contramap : ('b -> 'a) -> 'a testable -> 'b testable |
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Do you mind naming this map -- even if it doesn't follow the theory, that's what more users would expect :p
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What do you think about keeping the Fmt convention by calling it using? (Because I find that calling it map makes reading its signature ... complicated).
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Hm, btw you are right, map works well, fixed on 415abb4
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using could work too - no strong opinion between map and using
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Thanks that looks like a great addition! LGTM apart questions on names (the most difficult questions, as usual) |
MisterDA
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MisterDA
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Seq.uncons was introduced in OCaml 4.14. We may want to keep supporting OCaml 4.08 for a while still.
CHANGES: - Add `seq`, a testable for `Seq.t` and `contramap` (mirage/alcotest#412 @xvw) - Expose the `V1.Skip` exception (mirage/alcotest#415, mirage/alcotest#416, @Khady) - BREAKING FIX: `match_raises` now expects the user-defined function to return true for expected exceptions. Previously false was interpreted as an expected exception. (mirage/alcotest#418, mirage/alcotest#419, @psafont)
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This PR adds:
seq(to produces'a Seq.t testable) Because theSeq.ttype has become very common in the standard librarycontramapwhich allows you to go from an'a testableto a'b testablegiving a function fromb -> 'a(because a testable is a contravariant functor). I have often found the function useful for implementing testables quickly when there is a trivial transformation.