tisp

Unnamed repository; edit this file 'description' to name the repository.
git clone git://edryd.org/tisp
Log | Files | Refs | LICENSE

commit adc5c4e7b834c456ffaabec1ad1e4758d9592dd4
parent a0a2210693fa089417ca5b674384d4387f2e4ae4
Author: Ed van Bruggen <edvb@uw.edu>
Date:   Thu, 15 Mar 2018 23:32:26 -0700

Clean up hash_extend functions

Rename hash_extendh to hash_merge. Fix hash_merge from casueing a
segmentation fault on empty hash items

Diffstat:
tisp.c | 36++++++++++++++----------------------
1 file changed, 14 insertions(+), 22 deletions(-)

diff --git a/tisp.c b/tisp.c @@ -91,7 +91,7 @@ struct Val { /* functions */ static void hash_add(Hash ht, char *key, Val val); static void hash_extend(Hash ht, Val args, Val vals); -static void hash_extendh(Hash ht, Hash ht2); +static void hash_merge(Hash ht, Hash ht2); Val read_val(Str str); Val read_list(Str str); @@ -204,40 +204,32 @@ hash_add(Hash ht, char *key, Val val) } } +/* add each binding args[i] -> vals[i] */ +/* args and vals are both scheme lists */ static void hash_extend(Hash ht, Val args, Val vals) { - // add each binding args[i] -> vals[i] - // args and vals are both scheme lists - Val arg, val; - while (!nilp(args) && !nilp(vals)) { + for (; !nilp(args) && !nilp(vals); args = cdr(args), vals = cdr(vals)) { arg = car(args); val = car(vals); - args = cdr(args); - vals = cdr(vals); - if (arg->t != SYMBOL) { - fprintf(stderr, "Error in hash_extend: Argument not a symbol."); - exit(1); - } + if (arg->t != SYMBOL) + die(1, "%s: hash_extend: Argument not a symbol", argv0); hash_add(ht, arg->v.s, val); } } +/* add everything from ht2 into ht */ static void -hash_extendh(Hash ht, Hash ht2) +hash_merge(Hash ht, Hash ht2) { - // add everything from ht2 into ht - int i; - while (ht2) { - for (i = 0; i < ht2->cap; i++) { - hash_add(ht, ht2->items[i].key, ht2->items[i].val); - } - ht2 = ht2->next; - } + for (; ht2; ht2 = ht2->next) + for (i = 0; i < ht2->cap; i++) + if (ht2->items[i].key) + hash_add(ht, ht2->items[i].key, ht2->items[i].val); } Val @@ -454,9 +446,9 @@ tisp_trampoline(Hash env, Val v, int *continu) *continu = 0; return (*f->v.pr)(env, args); case FUNCTION: - // tail call into the function body with the extended env + /* tail call into the function body with the extended env */ hash_extend(env, f->v.f.args, args); - hash_extendh(env, f->v.f.env); + hash_merge(env, f->v.f.env); *continu = 1; return f->v.f.body; default: