Change AndThen to directly check isRightAssociated #3569
Merged
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fix #3568
The change to address the above is to avoid
equal
which on a very deep structure can blow the stack. Instead, directly check the property we want: isRightAssociated.I removed a microoptimization (using != instead of <) since I would be SHOCKED if that changed the perf of this code which has to do quite a bit of pattern matching already. The != is not very safe since if a refactor gets it wrong, it can easily blow past the limit.
Lastly, I couldn't resist a bit of refactoring to share more of the code and improve associations (still at O(1) cost per andThen/compose).
cc @travisbrown