[Flex-help] How to debug flex matching?

[Georgios P. <pet...@ya...>]

Hi all,

I am having trouble understanding why gnu flex does not match a specific 
string the way I think it should be matched.
And I don't know how to debug/trace how the match is done.

My rule set tries to implement a natural language tokenizer.

I have a rule that says:

syz\./[:space:] -> tag token as an abbreviation (lets name this "rule 1")

Further in the rule set, there is a rule that says:
{consonant}+/\.[:space:]+{capital} -> tag as word & split sentence

where {consonant} & {capital} are my definitions. (lets name this "rule 2")

I cannot understand why when matching string "syz. test" rule 1 is used 
(what I want), but when matching "syz. Test" rule 2 is matched (what I 
do not want). Rule 2 is not only after rule 1, but it also matches a 
shorter text (as the period is in the trailing context). Why is this 
happening?

I have tried the option "%option debug", but nothing is written in 
stderr (perhaps because I load the scanner as a dynamic library).

Regards,

George