[Flex-devel] Questions about functionality

[Joe K. <kr...@ni...>]

What part of the generated code is supposed to be visible to user code 
from section 1? My understanding is that section 1 is meant for 
including extra headers, and inserting cpp #defines to modify cpp-based 
options. However, it apparently does not come early enough in the 
generated code, because somebody added the %top{} feature.

My first guess is just to avoid moving any code to the other side of the 
current section 1 code insertion, to avoid breaking things. But, there 
should be some specific rules. In any case, the %top{} feature is useful 
because it gets written to the public header.

Why does the yylineno macro point to the buffer stack bs_lineno only in 
the reentrant scanner? Also, why not support yycolumn for the 
non-reentrant scanner?

Does anybody think that M4 macros should be accessible in user code? My 
version of the skeleton disables all m4 processing of user code. This 
fixes at least one bug in the bug tracker, but breaks some of the test 
scanners. To work around this, my skeleton also generates cpp macros to 
replace some of the M4 macros. This allows code with M4 macros to work, 
but avoids possible side-effects of m4 processing. Should these be 
enabled only for internal testing, or are some users writing scanners 
that use these? My idea is to add an option flag, but state that it is 
mainly intended for internal testing.

Joe Krahn