PInner Monoid instance in Plutarch.Orphans causes (plutarch-compile-time) infinite loops where (PInner a ~ a)

[t1lde]

See:

liqwid-plutarch-extra/src/Plutarch/Orphans.hs

Lines 54 to 68 in fe341f0

	-- | @since 1.3.0
	instance
	{-# OVERLAPPABLE #-}
	(Semigroup (Term s a), a ~ PInner b) =>
	Semigroup (Term s b)
	where
	(<>) = punsafeDowncast .* ((<>) `on` punsafeCoerce)
	-- | @since 1.3.0
	instance
	{-# OVERLAPPABLE #-}
	(Monoid (Term s a), a ~ PInner b) =>
	Monoid (Term s b)
	where
	mempty = punsafeDowncast mempty

This causes most types without Monoid/Semigroup instances to erroneously receive instances!

For example - the following cause an infinite loop at plutarch compile time:

printTerm (Config DoTracing) (d :: Term s PScriptContext)
printTerm (Config DoTracing) (d :: Term s PDatum)

This is due to most of the Builtin types having (PInner a ~ a), so effectively every type will cause such looping !

[peter-mlabs]

Fascinating. How did you track this down?