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[Ulrich Kühne <ulrichk AT informatik.uni-bremen.de>]

Hi,

I would like to parse a language which has keywords containing 
underscores '_'. Unfortunately, since the '_' is a special symbol in K, 
there seems to be no way of escaping it in the syntax rules and make it 
work as expected. Here is a minimal example:

module FOO
  syntax Foo ::= "foo_bar" Int
  syntax KResult ::= Int
  rule foo_bar X:Int => X
endmodule

What I get is an error message:

$> kompile foo
Some errors occurred..
sdf-load:error: parse error, '_' unexpected
--- input string [file: ./Program.sdf line: 11 col: 14]

I also tried things like "foo\_bar", but this doesn't work either. So an 
(unpleasant) workaround would entail preprocessing the source code in 
order to remove all underscores. There must be a better way, no?

Thanks in advance.
Ulrich

PS: A reference document would be great, listing all the builtins and 
operations. It took me quite some time to figure out the "X in 
keys(Map)" trick :-)