Re: Reachability of DFA part

On 2019-12-23, Christopher F Clark <christopher.f.clark@compiler-resources.com> wrote:
> Andy borucki.andrzej@gmail.com wrote:
>
>> Good definition would be {[^}]*}
>> Complexity of problem increases when comment ends with string
>> len >1, for example C: */ or Pascal *)
>> if we renaming : /->a *->b other->c
>> then bad definition will ab(a|b|b)*ba and good definition is
>> complicated:
>> ab(b|(a|c)*b*)*a (if I not make mistake)
>
>> Commments should maybe be defined in other way, especially
>> comments can be nested in Object Pascal.
>> Comment nesting can using stack or simply counter. I
>> see, in Pascal is using counter.
>> Difference: Pascal has two types of multiline comments { } and (* *)
>
> I'm not sure what kind of language you are trying to lex/parse, but
> the problems you are mentioning all have known solutions.


OP seems to be learning to construct a regex implementation geared
toward the generation of a lexical analyzer for any language.

Return to the comp.compilers page.
Search the comp.compilers archives again.