Re: SMIE grammar for C-style function expressions

[Nikolay Kudryavtsev]

I understand that SMIE does not concern itself with the AST, but I think 
it's reasonable to start with describing the language grammar for it in 
the most naive way, until we have a good reason not to. "f n ( a ) { s 
}" is a single expression in the language, so someone implementing a 
grammar for such language may first try to declare it in SMIE as a 
single expression.

To try and keep the problem stated in practical terms, lets say the 
language grammar looks like this:

args = ( a )

stmts = { s }

"f" n args stmts "f-end"

With the point after "f-end", I want backward-sexp to put me past "f" 
and for this:

(A)I have to keep the entire expression within a single SMIE declaration.

(B)My lexer has to add some virtual keywords to separate nonterminals:

"f" n " : " args " : " stmts "f-end"

Is this the proper approach? Are my assumptions A and B correct?

P. S. I've add "f-end" here to wave off the ambiguity caused by the last 
token in the real C-style expression being both main and child 
expression closer, since that problem, while real, is not the issue here.