It brings bison as a build dependency in case it is set the following way:
USES= bison or USES= bison:build
it brings bison as a run dependency in case it is set the following way:
USES= bison:run
it brings bison both as a run and build dependency in case it the set the following way:
USES= bison:both
While here trim some headers
Convert some USE_GNOME= gnomehack to USES= pathfix
Flex is a tool for generating scanners. A scanner, sometimes called a
tokenizer, is a program which recognizes lexical patterns in text. The
flex program reads user-specified input files, or its standard input
if no file names are given, for a description of a scanner to generate.
The description is in the form of pairs of regular expressions and C
code, called rules. Flex generates a C source file named, "lex.yy.c",
which defines the function yylex(). The file "lex.yy.c" can be compiled
and linked to produce an executable. When the executable is run, it
analyzes its input for occurrences of text matching the regular
expressions for each rule. Whenever it finds a match, it executes the
corresponding C code.
WWW: http://flex.sourceforge.net/
Note that there's flex 2.5.4 in the base system. This port provides
a newer version for programs that require it, textproc/xxdiff for one.
