b4_define_flag_if([glr]) # Whether a GLR parser is requested.
b4_define_flag_if([locations]) # Whether locations are tracked.
b4_define_flag_if([nondeterministic]) # Whether conflicts should be handled.
+b4_define_flag_if([pull]) # Whether pull parsing is requested.
b4_define_flag_if([pure]) # Whether the interface is pure.
-b4_define_flag_if([push]) # Whether push parsing is supported.
+b4_define_flag_if([push]) # Whether push parsing is requested.
b4_define_flag_if([yacc]) # Whether POSIX Yacc is emulated.