remove fauxMatch for tyFromExpr, remove tyProxy and tyUnknown aliases (#24018)

updated version of #22193

After #22029 and the followups #23983 and #24005 which fixed issues with
it, `tyFromExpr` no longer match any proc params in generic type bodies
but delay all non-matching calls until the type is instantiated.
Previously the mechanism `fauxMatch` was used to pretend that any
failing match against `tyFromExpr` actually matched, but prevented the
instantiation of the type until later.

Since this mechanism is not needed anymore for `tyFromExpr`, it is now
only used for `tyError` to prevent cascading errors and changed to a
bool field for simplicity. A change in `semtypes` was also needed to
prevent calling `fitNode` on default param values resolving to type
`tyFromExpr` in generic procs for params with non-generic types, as this
would try to coerce the expression into a concrete type when it can't be
instantiated yet.

The aliases `tyProxy` and `tyUnknown` for `tyError` and `tyFromExpr` are
also removed for uniformity.

1 files changed, 1 insertions, 1 deletions

diff --git a/lib/system/hti.nim b/lib/system/hti.nim
index 9acaae88b..a26aff982 100644
--- a/lib/system/hti.nim
+++ b/lib/system/hti.nim
@@ -59,7 +59,7 @@ type
     tyOwned, tyUnused1, tyUnused2,
     tyVarargsHidden,
     tyUncheckedArray,
-    tyProxyHidden,
+    tyErrorHidden,
     tyBuiltInTypeClassHidden,
     tyUserTypeClassHidden,
     tyUserTypeClassInstHidden,