-+ part of an include option. (The prefix is discarded before matching.)
-+
-+ it() if the pattern starts with ". " (a dot followed by a space) then its
-+ pattern is taken to be a merge-file that is read in to supplement the
-+ current rules. See the section on MERGED EXCLUDE FILES for more
-+ information.
-
- it() if the pattern is a single exclamation mark ! then the current
++ it() if the pattern starts with "+" (a plus), the actual pattern begins
++ after the first space, and is always considered to be an include pattern,
++ even if specified as part of an exclude file/option. Option letters may
++ follow the "+" prior to the separating space (see below).
++
++ it() if the pattern starts with "-" (a minus), the actual pattern begins
++ after the first space, and is always considered to be an exclude pattern,
++ even if specified as part of an include file/option. Option letters may
++ follow the "-" prior to the separating space (see below).
+
+- it() if the pattern is a single exclamation mark ! then the current
++ it() if the pattern is a "!" (single exclamation mark) then the current