Show errors for ambigious symbol

[alaviss]

Example:

import cligen, options

func get() = discard

dispatch get

This will fail due to ambiguous symbol get provided by both options and the current module, and the error message is certainly unhelpful:

nimble/pkgs/cligen-0.9.17/cligen.nim(215) dispatchGen
test.nim(5, 10) template/generic instantiation of `dispatch` from here
nimble/pkgs/cligen-0.9.17/cligen.nim(215, 19) Error: node is not a symbol

[c-blake]

First, I agree it's not a great error message for a common situation. However, the error message in question is not from me, but from Nim. It has recently changed to Error: node lacks field: symbol. It's also compile time messaging/erroring out not some run time exception I could catch. So, I'm not sure I have any control at all over what it says.

[alaviss]

You can check the node type beforehand. If it's nnk{Closed,Open}SymChoice (it was nnkClosedSymChoice in this case), then you can just print out every overload found with a nice error message.

A lazy approach is to use typed{nkSym} as the parameter to offload the job to the compiler. The error message would not be nice, but it's understandable.

[c-blake]

Ah. Good suggestions. Do you know a way at the macro call site to refer (more verbosely, obviously) to a specific get overload? If so, I could also put that in the error message as guidance.

[c-blake]

(I mean, of course, the type signature not just the module qualifier...)

[c-blake]

I went with the lazier typed{nkSym} approach. I agree it's an ugly error message, but I feel it's a better overall solution for you to submit an issue to Nim to get them to format it more nicely for everyone. See test/QualifiedSym.nim.