Add MonadFix instance #179
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This implementation doesn't make any attempt to be fusion-friendly. That would seem to require digging into some internals. Unfortunately, I tend to get rather lost in |
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I *believe* this is equivalent to the instance for `[]`. Writing QuickCheck properties for `mfix` seems pretty tricky, so I just added a small unit test. Fixes haskell#178
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I don't think being fused is a realistic goal for this. I'll try to look it over soon. |
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In case this helps: I just tested this implementation against the two list
monad examples in Levent Erkök's thesis, and it seems to check out.
…On Wed, Jul 5, 2017 at 9:31 PM, dolio ***@***.***> wrote:
I don't think being fused is a realistic goal for this.
I'll try to look it over soon.
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Do the properties of |
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I believe so. The only trouble is that we end up with an extra call to the
passed function. I don't *think* we save much complexity over a slightly
simplified version. I'll post one or two options later if I have time.
Please poke me if I haven't done so by Monday.
On Jul 15, 2017 11:47 AM, "dolio" <notifications@github.com> wrote:
Do the properties of mfix here mean that boostrapping with f ⊥ is just as
good as fix (head . f) (because we just want to know the 'statically
determined' length)? And then the generate is less complicated?
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Superseded by #312 |
Shimuuar
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It's #179 with merged into latest master and documentation tweaks Originally PR authored by David Feurer I *believe* this is equivalent to the instance for `[]`. Writing QuickCheck properties for `mfix` seems pretty tricky, so I just added a small unit test. Co-authored-by: David Feuer <David.Feuer@gmail.com>
lehins
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It's #179 with merged into latest master and documentation tweaks Originally PR authored by David Feurer I *believe* this is equivalent to the instance for `[]`. Writing QuickCheck properties for `mfix` seems pretty tricky, so I just added a small unit test. Co-authored-by: David Feuer <David.Feuer@gmail.com>
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I believe this is equivalent to the instance for
[]. WritingQuickCheck properties for
mfixseems pretty tricky, so I justadded a small unit test.
Fixes #178