Select syntax parse transform

Richard Carlsson <>
Thu Oct 25 18:21:12 CEST 2001


On Thu, 25 Oct 2001, Sean Hinde wrote:

> I do tend to agree that it shouldn't be needed but if something like
> this provides the friendly introduction to match syntax that gets
> people over the steep learning curve it probably jutifies the horror
> of epp!

Just to clarify things a bit: 'epp' is just a simple C-style (cpp-like)
token-level preprocessor, i.e., it transforms the token stream before
the parser sees it. (This is why it is horrible, although I admit that
it is useful as long as the compiler is not clever enough.)

'epp' has nothing to do with things like parse transforms, expansion of
record syntax into tuples, etc.; this is handled by the compiler proper
*after* parsing the token stream. This kind of transform is much "nicer"
because both the input and the output are well-formed Erlang programs.

	/Richard

Richard Carlsson ()   (This space intentionally left blank.)
E-mail: 	WWW: http://www.csd.uu.se/~richardc/




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