shoddy dict implemented properly

diff --git a/src/dict.c b/src/dict.c
index 7ff7bb558119b33969f9b5625360f892362d2ba7..fc2053e3c445af288d5fadce8122106379da1e29 100644 (file)
--- a/src/dict.c
+++ b/src/dict.c
@@ -3,8 +3,7 @@
 #include "sexpr.h"
 #include "dict.h"
 
-#define HT_SIZE (2<<16)
-
+#include <stdio.h>
 
 // okay, doing an incredibly /incredibly/ naive dict implementation for now,
 // proper hash tables come later
@@ -17,23 +16,19 @@ Sexpr* init_dict() {
 
 Sexpr* append_to_dict(Sexpr* dict, Sexpr* key, Sexpr* value) {
        // assumes dict well-formed, returns new dict
+       // puts new things on the front of the dict, makes it so looking up gets the newest stuff first
        Sexpr* new = cons(key, value);
        return cons(new, dict);
 }
 
-
-
-
-
-uint64_t hash(char* s) {
-       uint64_t hash = 0;
-       uint64_t p = 31;
-       uint64_t p_to_pow = 1;
-       uint64_t m = HT_SIZE;
-       if(s==NULL) return hash;
-       while(*s != '\0') {
-               hash = (hash + p_to_pow*(*s - 'A'+1)) % m;
-               p_to_pow = (p_to_pow*p) % m;
+Sexpr* lookup(Sexpr* dict, Sexpr* key) {
+       // assumes dict well-formed
+       Sexpr* node = dict;
+               while(node->type != NIL) {
+                       if(equal(key, car(car(node)))->type == T) {
+                               return cdr(car(node));
+                       }
+                       node = cdr(node);
        }
-       return hash;
+       return from_nil();
 }

diff --git a/src/dict.h b/src/dict.h
index 612078a9a06b7e56eaddfc1a491ab83e30f0bdef..fe1aeeac19d8cebbb66331243dfe5dc7119dfbef 100644 (file)
--- a/src/dict.h
+++ b/src/dict.h
@@ -9,12 +9,8 @@
 
 // key type is string, value type is sexpr, hash range is uint64_t
 
-typedef struct KV_Pair {
-       uint64_t key;
-       Sexpr* val;
-} KV_Pair_t;
-
-uint64_t hash(char* s);
-
+Sexpr* init_dict();
+Sexpr* append_to_dict(Sexpr* dict, Sexpr* key, Sexpr* value);
+Sexpr* lookup(Sexpr* dict, Sexpr* key);
 
 #endif

diff --git a/src/sexpr.c b/src/sexpr.c
index 01286af9885400857d2d42a939aca94ae2baa5c6..126b1248c370372de425f9f881e6cf5e7a720df9 100644 (file)
--- a/src/sexpr.c
+++ b/src/sexpr.c
@@ -14,6 +14,14 @@ Sexpr* from_nil() {
        return ret;
 }
 
+Sexpr* from_t() {
+       Sexpr* ret = malloc(sizeof(Sexpr));
+       ret->type = T;
+       ret->value.t = NULL;
+       return ret;
+}
+
+
 Sexpr* from_sym(char* s) {
        Sexpr* ret = malloc(sizeof(Sexpr));
        ret->type = SYM;
@@ -46,6 +54,24 @@ Sexpr* cdr(Sexpr* s) {
        return s->value.c->cdr;
 }
 
+Sexpr* equal(Sexpr* a, Sexpr* b) {
+       // need to change later with proper builtins and so forth
+       if(a->type != b->type)
+               return from_nil();
+       Sexpr_Type t = a->type;
+       if(t == NIL)
+               return from_t();
+       if(t == T)
+               return from_t();
+
+       if(t == SYM) {
+               return strcmp(a->value.s, b->value.s) == 0 ? from_t() : from_nil();
+       }
+       // leaving everything else off for... reasons
+       return from_nil();
+}
+
+
 
 Sexpr* reverse(Sexpr* s) {
        if(s->type != CONS) {

diff --git a/src/sexpr.h b/src/sexpr.h
index 4bc42d3c52913600e8dd544d846b5dc2265f0d21..335c4b9ea764f7834727d4caf3efd8e170f1a747 100644 (file)
--- a/src/sexpr.h
+++ b/src/sexpr.h
@@ -6,6 +6,8 @@
 
 Sexpr* from_nil();
 
+Sexpr* from_t();
+
 Sexpr* from_sym(char* s);
 
 Sexpr* from_uint(uint64_t u);
@@ -18,6 +20,8 @@ Sexpr* cdr(Sexpr* s);
 
 Sexpr* reverse(Sexpr* s);
 
+Sexpr* equal(Sexpr* a, Sexpr* b);
+
 char* sprint_sexpr(Sexpr* s);
 
 #endif

diff --git a/src/test.c b/src/test.c
index 01277d0d507b226bce87210c6c6068933f3d4c05..550e6fb9fb9ae8d9bb4dd20302fe5a503f34542e 100644 (file)
--- a/src/test.c
+++ b/src/test.c
@@ -5,6 +5,7 @@
 #include "types.h"
 #include "sexpr.h"
 #include "parser.h"
+#include "dict.h"
 
 
 
@@ -66,11 +67,33 @@ void test_parser() {
        printf("_: %s\n", sprint_sexpr(parse("(a b (3 2 (5) c) d (e f) g)")));
 }
 
+void test_eq() {
+       printf("testing eq\n");
+       printf("t: %s\n", sprint_sexpr(from_t()));
+       Sexpr* a = from_sym("test");
+       Sexpr* b = from_sym("test");
+       printf("%s\n", sprint_sexpr(equal(a, b)));
+}
+
+void test_dict() {
+       printf("testing dict\n");
+       Sexpr* d = init_dict();
+       d = append_to_dict(d, from_sym("hello"), from_sym("world"));
+       d = append_to_dict(d, from_sym("asdf"), from_uint(544));
+       printf("lookup hello: %s\n", sprint_sexpr(lookup(d, from_sym("hello"))));
+       printf("lookup asdf: %s\n", sprint_sexpr(lookup(d, from_sym("asdf"))));
+
+
+}
+
+
 void run_tests(){
-       test_basics();
-       test2();
-       test_parsing();
-       test_parser();
+       //test_basics();
+       //test2();
+       //test_parsing();
+       //test_parser();
+       //test_eq();
+       test_dict();
 }
 
 int main() {