Overly humble error message for cannot-apply

[masak]

Using the Windows executable of the 0.4.0 release:

$ ./chime.exe
> (nil)
I don't know how to evaluate this yet: (nil)

Two issues:

• Phrasing: "yet" makes it sound like the evaluator is missing a case, the presence of which would allow it to handle (nil). That is not so; (nil) tries to apply a nil, which can not be applied. Chime is accepting blame for something that is not its fault. (Maybe this phrasing made more sense during active development.)

• What's more relevant here is the value that causes the 'cannot-apply error — but the failing value is not printed, only the expression. In a debugging situation, the value is likely to be the much more important detail, basically answering "why did this call fail?". A second example might help here:

> (set foo "not a function, but a string")
"not a function, but a string"

> (foo 1 2 3)
I don't know how to evaluate this yet: (foo 1 2 3)