Implement deriveEnumData

[bezirg]

Add to deriveEnum a more efficient implementation of IsData classes.

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[github-actions]

Execution Budget Golden Diff

85ce1fd (master) vs 54249f0

output

This comment will get updated when changes are made.

[zliu41]

Why do we still need deriveEnum given deriveEnumData?

[bezirg]

Why do we still need deriveEnum given deriveEnumData?

Because there are existing datatypes like Bool, that have the old less-efficient encoding, and I didn't want to break compatibility with those.

If u think we can get away with breaking the encoding of Bool and () , then deriveEnum can be removed.

I am worried that the ledger-api relies on these old encodings

[zliu41]

We can't break the encoding of Bool and (), but how many types need deriveEnum? If there are only a few, then it is far easier to write their instances manually than writing the TH code for deriveEnum.

[bezirg]

We can't break the encoding of Bool and (), but how many types need deriveEnum?

About the encoding, i think you are right, no context depends on it , so we can switch to deriveenumdata and get rid of deriveenum