From acdffdb31d8f8f5610a7188b261fe4112ea5691a Mon Sep 17 00:00:00 2001
From: Elijah Cohen <eli@eli173.com>
Date: Mon, 22 Jul 2024 12:28:36 -0500
Subject: [PATCH] shoddy dict implemented properly

---
 src/dict.c  | 27 +++++++++++----------------
 src/dict.h  | 10 +++-------
 src/sexpr.c | 26 ++++++++++++++++++++++++++
 src/sexpr.h |  4 ++++
 src/test.c  | 31 +++++++++++++++++++++++++++----
 5 files changed, 71 insertions(+), 27 deletions(-)

diff --git a/src/dict.c b/src/dict.c
index 7ff7bb5..fc2053e 100644
--- 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 612078a..fe1aeea 100644
--- 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 01286af..126b124 100644
--- 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 4bc42d3..335c4b9 100644
--- 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 01277d0..550e6fb 100644
--- 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() {
-- 
2.39.2