diff options
Diffstat (limited to 'src/scheme/ao_scheme_cons.c')
| -rw-r--r-- | src/scheme/ao_scheme_cons.c | 38 |
1 files changed, 37 insertions, 1 deletions
diff --git a/src/scheme/ao_scheme_cons.c b/src/scheme/ao_scheme_cons.c index 21ee10cc..02512e15 100644 --- a/src/scheme/ao_scheme_cons.c +++ b/src/scheme/ao_scheme_cons.c @@ -112,7 +112,7 @@ ao_scheme_cons_cdr(struct ao_scheme_cons *cons) if (cdr == AO_SCHEME_NIL) return NULL; if (ao_scheme_poly_type(cdr) != AO_SCHEME_CONS) { - (void) ao_scheme_error(AO_SCHEME_INVALID, "improper list"); + (void) ao_scheme_error(AO_SCHEME_INVALID, "improper cdr %v", cdr); return NULL; } return ao_scheme_poly_cons(cdr); @@ -124,6 +124,42 @@ ao_scheme__cons(ao_poly car, ao_poly cdr) return ao_scheme_cons_poly(ao_scheme_cons_cons(car, cdr)); } +struct ao_scheme_cons * +ao_scheme_cons_copy(struct ao_scheme_cons *cons) +{ + struct ao_scheme_cons *head = NULL; + struct ao_scheme_cons *tail = NULL; + + while (cons) { + struct ao_scheme_cons *new; + ao_poly cdr; + + ao_scheme_cons_stash(0, cons); + ao_scheme_cons_stash(1, head); + ao_scheme_poly_stash(0, ao_scheme_cons_poly(tail)); + new = ao_scheme_alloc(sizeof (struct ao_scheme_cons)); + cons = ao_scheme_cons_fetch(0); + head = ao_scheme_cons_fetch(1); + tail = ao_scheme_poly_cons(ao_scheme_poly_fetch(0)); + if (!new) + return AO_SCHEME_NIL; + new->car = cons->car; + new->cdr = AO_SCHEME_NIL; + if (!head) + head = new; + else + tail->cdr = ao_scheme_cons_poly(new); + tail = new; + cdr = cons->cdr; + if (ao_scheme_poly_type(cdr) != AO_SCHEME_CONS) { + tail->cdr = cdr; + break; + } + cons = ao_scheme_poly_cons(cdr); + } + return head; +} + void ao_scheme_cons_free(struct ao_scheme_cons *cons) { |