f_expt             40 ext/date/date_core.c #define f_expt(x,y) rb_funcall(x, rb_intern("**"), 1, y)
f_expt             21 ext/date/date_parse.c #define f_expt(x,y) rb_funcall(x, rb_intern("**"), 1, y)
f_expt             45 ext/date/date_strptime.c #define f_expt(x,y) rb_funcall(x, rb_intern("**"), 1, y)