On 17/03/2009, at 1:13 PM, Jonathan Cast wrote:
[Totally OT tangent: How did operational semantics come to get its noun? The more I think about it, the more it seems like a precís of the implementation, rather than a truly semantic part of a language specification.]
I haven't followed the whole thread, so perhaps I'm missing some important context to this question. It is true that operational semantics are often used to summarise or explain an _implementation_ of a language feature, but I wouldn't say that they are always used in this way. An operational semantics may be used to define a "behaviour" function: (program x input) -> outcome. The big-step style of operational semantics style tends to be less like an implementation, and more like a specification. Perhaps the more crucial part of operational semantics is that it just deals with syntactic terms as its "values". Apologies if this has nothing to do with your question. Cheers, Bernie.