/* e_25_6.t:    Macro arguments are pre-expanded separately.    */

#define sub( x, y)      (x - y)

/* 25.6:    */

#define head            sub(

#define body(x,y)       x,y

#define tail            )

#define head_body_tail( a, b, c)    a b c

/* "head" is once replaced to "sub(", then rescanning of "sub(" causes an

        uncompleted macro call.  Expansion of an argument should complete

        within the argument.    */

    head_body_tail( head, body(a,b), tail);