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Plutonomicon / plutarch-plutus

Typed eDSL for writing UPLC /ˈpluː.tɑːk/
MIT License
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Make ptruncate use pquot instead of emulating it #594

Closed cjay closed 2 years ago

L-as commented 2 years ago

Are we sure QuotientInteger has the same semantics?

cjay commented 2 years ago

I haven't found a specification of what the builtin is supposed to do exactly, but the existing tests would catch if it rounded differently, so pretty sure it behaves like quot in Haskell.

tests/Plutarch/RationalSpec.hs
4:import Plutarch.Rational (pproperFraction, ptruncate)
32:      "5/4" @| ptruncate # rat (5 / 4) @== pconstant @PInteger 1
33:      "7/4" @| ptruncate # rat (7 / 4) @== pconstant @PInteger 1
34:      "1/4" @| ptruncate # rat (1 / 4) @== pconstant @PInteger 0
35:      "-7/4" @| ptruncate # rat (-7 / 4) @== pconstant @PInteger (-1)
L-as commented 2 years ago

you can check the implementation

cjay commented 2 years ago

If PlutusTx.Builtins.Internal is the right place: quotientInteger makes use of the normal quot.