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Re: Bug in SableCC 2.17.2?
Xuan Baldauf wrote:
> Where can I find documentation about the grammar definition file
> format (except the thesis and the example grammars)?
This is probably not what you want, but the grammar itself is described
as a SableCC grammar in one of the examples. The best reference (with
explanations) are chapters 5 & 6 in the thesis... And there's always
this list to ask for clarifications;-)
> Are there any difference between a "set of alternatives of characters"
> and a "set of characters" in using them? (Does the former have
> advantages that the latter cannot have and vice versa?)
The advantage of using set of characters is the "-" operator that is not
available to "regular expressions". This will eventually change in
SableCC 3.x. The other advantage is the availability of "ranges" e.g.
['a'..'z'] which would be otherwise quite annoying to write 'a' | 'b' |
'c' | etc.
> With the current syntax, I have to write this (which is ugly):
> separators =
> '(' +
This will also change in SableCC 3.x... (The difference between sets and
reg.exp. will disappear along the "+" operator. You'll simply write:
xxx = (['a' .. 'z'] | ['A' .. 'Z'] | ['0' .. 10]) - ('3' | 'b' | 'F');
identifier = (['a' .. 'z'] (['a' .. 'z'] | ['0' .. '9'])*) - 'hello';
Neat, isn't it? Yep, I'll have to do the dirty work to make this
But, this is not for tommorrow... I'm just letting you (and myself)
dream a little:)
P.S. Big thanks to Mariusz for the quick modifications. I like youe
"magic" debugging property a lot.
Etienne M. Gagnon firstname.lastname@example.org