Files
Nim/tests/generics/tpointerprocs.nim
metagn 0a058a6b8f better errors for standalone explicit generic instantiations (#24276)
refs #8064, refs #24010

Error messages for standalone explicit generic instantiations are
revamped. Failing standalone explicit generic instantiations now only
error after overloading has finished and resolved to the default `[]`
magic (this means `[]` can now be overloaded for procs but this isn't
necessarily intentional, in #24010 it was documented that it isn't
possible). The error messages for failed instantiations are also no
longer a simple `cannot instantiate: foo` message, instead they now give
the same type mismatch error message as overloads with mismatching
explicit generic parameters.

This is now possible due to the changes in #24010 that delegate all
explicit generic proc instantiations to overload resolution. Old code
that worked around this is now removed. `maybeInstantiateGeneric` could
maybe also be removed in favor of just `explicitGenericSym`, the `result
== n` case is due to `explicitGenericInstError` which is only for niche
cases.

Also, to cause "ambiguous identifier" error messages when the explicit
instantiation is a symchoice and the expression context doesn't allow
symchoices, we semcheck the sym/symchoice created by
`explicitGenericSym` with the given expression flags.

#8064 isn't entirely fixed because the error message is still misleading
for the original case which does `values[1]`, as a consequence of
#12664.
2024-10-18 19:06:42 +02:00

36 lines
976 B
Nim

discard """
cmd: "nim check $options --hints:off $file"
action: "reject"
nimout:'''
tpointerprocs.nim(22, 11) Error: 'foo' doesn't have a concrete type, due to unspecified generic parameters.
tpointerprocs.nim(34, 14) Error: type mismatch: got <int>
but expected one of:
proc foo(x: int | float; y: int or string): float
first type mismatch at position: 2 in generic parameters
missing generic parameter: y:type
expression: foo[int]
tpointerprocs.nim(34, 14) Error: cannot instantiate: 'foo[int]'
tpointerprocs.nim(34, 14) Error: expression 'foo[int]' has no type (or is ambiguous)
tpointerprocs.nim(35, 11) Error: expression 'bar' has no type (or is ambiguous)
'''
"""
block:
proc foo(x: int | float): float = result = 1.0
let
bar = foo
baz = bar
block:
proc foo(x: int | float): float = result = 1.0
let
bar = foo[int]
baz = bar
block:
proc foo(x: int | float, y: int or string): float = result = 1.0
let
bar = foo[int]
baz = bar