map.LookupByNode reports unhelpful error when given a badly typed input

[dustmop]

See c252ec2#diff-01ef2f316335ee972d15e3ff4c13fc77f11790911033d21c03b5155f10284922R242

The method LookupByNode on map expects its argument to be a string. If a bad value such as a number is passed in, the error message is unclear as to the real problem. For example, when map.LookupByNode(basicnode.NewInt(3)) is called, the error is func called on wrong kind: "AsString" called on a int node (kind: int), but only makes sense on string. This is because the parameter is coerced to a string and that error bubbles up to the caller. It would be better if the error were something like LookupByNode needs a string parameter, got (kind: int), letting the caller know exactly what they are doing wrong.

Many other methods on other types have similar issues.

[ahmedmustafamo]

@dustmop "...Many other methods on other types have similar issues."
please provide the description with the other methods to apply the error messages on them

[dustmop]

@AhmedMustafa2201 My apologies, I haven't worked on this codebase in about a year and don't recall what this comment is referring to. I'm sure fixing just the single error message would be a helpful improvement.