Wolfgang Jeltsch wolfgang-it at
Thu Sep 7 01:54:46 UTC 2017

Am Samstag, den 02.09.2017, 14:08 -0500 schrieb Jonathan S:
> I think that in addition to nesting and sliding, we should have the
> following law:
> ffix (\x -> fmap (f x) g) = fmap (\y -> fix (\x -> f x y)) g
> I guess I'd call this the "pure left shrinking" law because it is the
> composition of left shrinking and purity:

I wonder whether “pure left shrinking” is an appropriate name for this.
The shrinking is on the left, but the purity is on the right. Note that
in “pure right shrinking”, a derived property discussed in Erkok’s
thesis, both the shrinking and the purity are on the right.

All the best,

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