substitute
v_evaluate(&v, substitute(sp, 0),
# define PS4_SUBSTITUTE(s) substitute((s), 0)
prompt = str_save(substitute(tmp, 0), saved_atemp);
shellf("%s\n", substitute(mbp->mb_msg ? mbp->mb_msg : MBMESSAGE, 0));
substitute(initsubs, 0);
include(substitute("$HOME/.profile", 0), 0, NULL, 1);
env_file = substitute(env_file, DOTILDE);
char * substitute(const char *, int);
sub = substitute(tmp, 0);
sdone |= substitute(cp);
static int substitute(struct s_command *);