Not all reductions reduce from the same sort to the same value.

Question: what is a good syntax?

Submitted by Eelco Visser on 20 May 2014 at 09:58

Implemented. The new (temporary) syntax is:

module foo
signature
   arrows
      Term --name> Term

rules
    x --name> y

The default rule is called --> which is desugared to --default> and must be explicitly declared. Example

module foo
signature
   arrows
      Term --> Value

pretty it is not

perhaps adding an extra - or adding the - to before the > makes the arrow impression stronger; but I suppose typical rule names will be one letter

module foo
signature
arrows
Term -name-> Term
Term -e-> Term

rules
x -name-> y

Foo(x, y) -e-> Bar()
where x -e-> Z(), y -f-> h

And how does this interact with the syntax for emitted signals?

Indeed it isn’t pretty. I changed syntax to have an additional -. New syntax (with emitted signals) is as follows:

module foo
....
arrows
   Term -name-> Term

rules

  x -L msg, E ex-n-> y

  x --> y

  x -n-> y

  x -L msg, E ex-> y