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-rw-r--r--eval.c353
1 files changed, 163 insertions, 190 deletions
diff --git a/eval.c b/eval.c
index d71ebc6..f48937f 100644
--- a/eval.c
+++ b/eval.c
@@ -1,5 +1,4 @@
#include "eval.h"
-#include "list.h"
#include "atom.h"
#include "parse.h"
#include "env.h"
@@ -7,7 +6,7 @@
#include <stdio.h>
#include <string.h>
-static int atom_cmp(struct list *a, struct list *b)
+static int atom_cmp(struct atom *a, struct atom *b)
{
if (ATOM_TYPE(a) != ATOM_TYPE(b))
return 0;
@@ -35,20 +34,20 @@ static int atom_cmp(struct list *a, struct list *b)
switch (ATOM_TYPE(a))
{
case ATOM_INT:
- if (LIST_GET_ATOM(a)->l != LIST_GET_ATOM(b)->l)
+ if (a->l != b->l)
result = 0;
break;
case ATOM_STR:
case ATOM_SYMBOL:
- if (strcmp(LIST_GET_ATOM(a)->str.str, LIST_GET_ATOM(b)->str.str) != 0)
+ if (strcmp(a->str.str, b->str.str) != 0)
result = 0;
break;
case ATOM_LIST:
{
- struct list *ai = LIST_GET_ATOM(a)->list;
- struct list *bi = LIST_GET_ATOM(b)->list;
+ struct atom *ai = LIST_FIRST(a->list);
+ struct atom *bi = LIST_FIRST(b->list);
while (ai && bi)
{
@@ -58,8 +57,8 @@ static int atom_cmp(struct list *a, struct list *b)
break;
}
- ai = ai->next;
- bi = bi->next;
+ ai = LIST_NEXT(ai, entries);
+ bi = LIST_NEXT(bi, entries);
}
if (ai != NULL || bi != NULL)
@@ -72,225 +71,198 @@ static int atom_cmp(struct list *a, struct list *b)
return result;
}
-struct list *eval(struct list *list)
-{
- struct list env;
- memset(&env, 0, sizeof(env));
- return eval_env(list, &env);
-}
-
-struct list *eval_str(const char *str)
-{
- struct list env;
- memset(&env, 0, sizeof(env));
- return eval_str_env(str, &env);
-}
-
-struct list *eval_env(struct list *expr, struct list *env)
+struct atom *eval(struct atom *expr, struct env *env)
{
if (IS_SYM(expr))
{
- struct atom *atom = env_lookup(env, LIST_GET_ATOM(expr)->str.str);
+ struct atom *atom = env_lookup(env, expr->str.str);
if (atom)
{
- return list_append(NULL, atom);
+ return atom;
}
else
{
printf("error: undefined variable: %s\n",
- LIST_GET_ATOM(expr)->str.str);
- return list_append(NULL, &nil_atom);
+ expr->str.str);
+ return &nil_atom;
}
}
if (!IS_LIST(expr))
return expr;
- struct list *l = LIST_GET_ATOM(expr)->list;
+ struct list *list = expr->list;
+
+ struct atom *op = LIST_FIRST(list);
- if (IS_SYM(l))
+ if (strcmp(op->str.str, "quote") == 0)
{
- const char *sym = LIST_GET_ATOM(l)->str.str;
+ return atom_clone(LIST_NEXT(op, entries));
+ }
+ else if (strcmp(op->str.str, "atom") == 0)
+ {
+ struct atom *a = LIST_NEXT(op, entries);
- if (strcmp(sym, "quote") == 0)
- {
- return l->next;
- }
- else if (strcmp(sym, "atom") == 0)
+ if (!a)
+ return &nil_atom;
+
+ if (IS_LIST(a))
+ return &false_atom;
+ else
+ return &true_atom;
+ }
+ else if (strcmp(op->str.str, "eq") == 0)
+ {
+ struct atom *a = CDR(op);
+ struct atom *b = CDR(a);
+
+ if (!a || !b)
{
- if (IS_LIST(l->next))
- {
- return list_append(NULL, &false_atom);
- }
- else
- {
- return list_append(NULL, &true_atom);
- }
+ printf("error: eq takes 2 arguments\n");
+ return &nil_atom;
}
- else if (strcmp(sym, "eq") == 0)
- {
- struct list *a = CDR(l);
- struct list *b = CDR(a);
- if (!a || !b)
- {
- printf("error: eq takes 2 arguments\n");
- return list_append(NULL, &nil_atom);
- }
+ a = eval(a, env);
+ b = eval(b, env);
- a = eval_env(a, env);
- b = eval_env(b, env);
+ if (atom_cmp(a, b))
+ return &true_atom;
- if (atom_cmp(a, b))
- return list_append(NULL, &true_atom);
+ return &false_atom;
+ }
+ else if (strcmp(op->str.str, "+") == 0 ||
+ strcmp(op->str.str, "-") == 0 ||
+ strcmp(op->str.str, "/") == 0 ||
+ strcmp(op->str.str, "*") == 0)
+ {
+ struct atom *a = CDR(op);
+ struct atom *b = CDR(a);
- return list_append(NULL, &false_atom);
- }
- else if (strncmp(sym, "+", 1) == 0 ||
- strncmp(sym, "-", 1) == 0 ||
- strncmp(sym, "/", 1) == 0 ||
- strncmp(sym, "*", 1) == 0)
+ if (!a || !b)
{
- struct list *oper = CAR(l);
- struct list *a = CDR(oper);
- struct list *b = CDDR(oper);
-
- if (!a || !b)
- return list_append(NULL, &nil_atom);
-
- a = eval_env(a, env);
- b = eval_env(b, env);
+ printf("error: %s takes 2 arguments\n", op->str.str);
+ return &nil_atom;
+ }
- if (!(ATOM_TYPE(a) == ATOM_TYPE(b) && ATOM_TYPE(a) == ATOM_INT))
- return list_append(NULL, &nil_atom);
+ a = eval(a, env);
+ b = eval(b, env);
- long numa = LIST_GET_ATOM(a)->l;
- long numb = LIST_GET_ATOM(b)->l;
- long numr;
+ if (!(ATOM_TYPE(a) == ATOM_TYPE(b) && ATOM_TYPE(a) == ATOM_INT))
+ return &nil_atom;
- switch (*sym)
- {
- case '+':
- numr = numa + numb;
- break;
- case '-':
- numr = numa - numb;
- break;
- case '/':
- numr = numa / numb;
- break;
- case '*':
- numr = numa * numb;
- break;
- }
+ switch (*op->str.str)
+ {
+ case '+': return atom_new_int(a->l + b->l);
+ case '-': return atom_new_int(a->l - b->l);
+ case '/': return atom_new_int(a->l / b->l);
+ case '*': return atom_new_int(a->l * b->l);
+ }
- struct list *result = list_append(NULL, atom_new_int(numr));
+ return &nil_atom;
+ }
+ else if (strcmp(op->str.str, ">") == 0)
+ {
+ struct atom *a = CDR(op);
+ struct atom *b = CDR(a);
- return result;
- }
- else if (strncmp(sym, ">", 1) == 0)
+ if (!a || !b)
{
- struct list *oper = CAR(l);
- struct list *a = CDR(oper);
- struct list *b = CDDR(oper);
+ printf("error: > takes 2 arguments\n");
+ return &nil_atom;
+ }
- if (!a || !b)
- return list_append(NULL, &nil_atom);
+ a = eval(a, env);
+ b = eval(b, env);
- a = eval_env(a, env);
- b = eval_env(b, env);
+ if (!(ATOM_TYPE(a) == ATOM_TYPE(b) && ATOM_TYPE(a) == ATOM_INT))
+ return &nil_atom;
- if (!(ATOM_TYPE(a) == ATOM_TYPE(b) && ATOM_TYPE(a) == ATOM_INT))
- return list_append(NULL, &nil_atom);
+ if (a->l > b->l)
+ return &true_atom;
- long numa = LIST_GET_ATOM(a)->l;
- long numb = LIST_GET_ATOM(b)->l;
+ return &false_atom;
+ }
+ else if (strcmp(op->str.str, "if") == 0)
+ {
+ struct atom *predicate = CDR(op);
+ struct atom *true_case = CDR(predicate);
+ struct atom *false_case = CDR(true_case);
- if (numa > numb)
- return list_append(NULL, &true_atom);
- else
- return list_append(NULL, &false_atom);
- }
- else if (strcmp(sym, "if") == 0)
+ if (!predicate || !true_case || !false_case)
{
- struct list *predicate = CDR(l);
- struct list *true_case = CDR(predicate);
- struct list *false_case = CDR(true_case);
-
- if (!predicate || !true_case || !false_case)
- return list_append(NULL, &nil_atom);
-
- predicate = eval_env(predicate, env);
-
- if (IS_TRUE(predicate))
- return eval_env(true_case, env);
- else
- return eval_env(false_case, env);
+ printf("error: if takes 3 arguments\n");
+ return &nil_atom;
}
- else if (strcmp(sym, "mod") == 0)
- {
- struct list *a = CDR(l);
- struct list *b = CDR(a);
- if (!a || !b)
- {
- printf("error: mod takes two arguments\n");
- return list_append(NULL, &nil_atom);
- }
-
- a = eval_env(a, env);
- b = eval_env(b, env);
+ predicate = eval(predicate, env);
- if (!IS_INT(a) || !IS_INT(b))
- {
- printf("error: mod arguments must be integers\n");
- return list_append(NULL, &nil_atom);
- }
+ if (IS_TRUE(predicate))
+ return eval(true_case, env);
- long result = LIST_GET_ATOM(a)->l % LIST_GET_ATOM(b)->l;
+ return eval(false_case, env);
+ }
+ else if (strcmp(op->str.str, "mod") == 0)
+ {
+ struct atom *a = CDR(op);
+ struct atom *b = CDR(a);
- return list_append(NULL, atom_new_int(result));
+ if (!a || !b)
+ {
+ printf("error: mod takes two arguments\n");
+ return &nil_atom;
}
- else if (strcmp(sym, "define") == 0)
+
+ a = eval(a, env);
+ b = eval(b, env);
+
+ if (!IS_INT(a) || !IS_INT(b))
{
- struct list *expr_name = CDR(l);
- struct list *expr_value = CDR(expr_name);
+ printf("error: mod arguments must be integers\n");
+ return &nil_atom;
+ }
- if (!expr_name || !expr_value)
- {
- printf("error: define takes two arguments\n");
- return list_append(NULL, &nil_atom);
- }
+ return atom_new_int(a->l % b->l);
+ }
+ else if (strcmp(op->str.str, "define") == 0)
+ {
+ struct atom *expr_name = CDR(op);
+ struct atom *expr_value = CDR(expr_name);
- if (!IS_SYM(expr_name))
- {
- printf("error: define: first arg must be symbol\n");
- return list_append(NULL, &nil_atom);
- }
+ if (!expr_name || !expr_value)
+ {
+ printf("error: define takes two arguments\n");
+ return &nil_atom;
+ }
- expr_value = eval_env(expr_value, env);
+ if (!IS_SYM(expr_name))
+ {
+ printf("error: define: first arg must be symbol\n");
+ return &nil_atom;
+ }
- env_set(env, LIST_GET_ATOM(expr_name)->str.str,
- LIST_GET_ATOM(expr_value));
+ expr_value = eval(expr_value, env);
- return list_append(NULL, expr_value);
+ if (!env_set(env, expr_name->str.str, expr_value))
+ {
+ printf("error: cannot redefine %s\n", expr_name->str.str);
+ return &nil_atom;
}
+
+ return expr_value;
}
- else if (IS_LIST(l))
- {
- return eval(l);
- }
- return list_append(NULL, &nil_atom);
+ printf("error: unknown function %s\n", op->str.str);
+
+ return &nil_atom;
}
-struct list *eval_str_env(const char *expr, struct list *env)
+struct atom *eval_str(const char *expr, struct env *env)
{
- struct list *result;
+ struct atom *result;
int pos = 0;
- result = eval_env(parse(expr, &pos), env);
+ result = eval(parse(expr, &pos), env);
return result;
}
@@ -301,46 +273,48 @@ struct list *eval_str_env(const char *expr, struct list *env)
TEST(nested_expression)
{
- struct list *result = eval_str("(eq #f (> (- (+ 1 3) (* 2 (mod 7 4))) 4))");
+ struct env *env = env_new();
+ struct atom *result = eval_str("(eq #f (> (- (+ 1 3) (* 2 (mod 7 4))) 4))", env);
ASSERT_TRUE(result != NULL);
ASSERT_TRUE(IS_TRUE(result));
}
TEST(basic_if)
{
- struct list *result = eval_str("(if #t 42 1000)");
+ struct env *env = env_new();
+ struct atom *result = eval_str("(if #t 42 1000)", env);
+ print_atom(result, 0);
ASSERT_TRUE(result != NULL);
ASSERT_EQ(ATOM_INT, ATOM_TYPE(result));
- ASSERT_EQ(42, LIST_GET_ATOM(result)->l);
+ ASSERT_EQ(42, result->l);
}
TEST(if_with_sub_expressions)
{
- struct list *result = eval_str("(if (> 1 2) (- 1000 1) (+ 40 (- 3 1)))");
+ struct env *env = env_new();
+ struct atom *result = eval_str("(if (> 1 2) (- 1000 1) (+ 40 (- 3 1)))", env);
ASSERT_TRUE(result != NULL);
ASSERT_EQ(ATOM_INT, ATOM_TYPE(result));
- ASSERT_EQ(42, LIST_GET_ATOM(result)->l);
+ ASSERT_EQ(42, result->l);
}
-/* EVALUTE WITH ENVIRONMENT TESTS */
-
TEST(evaluate_symbol)
{
- struct list *env = env_new();
+ struct env *env = env_new();
env_set(env, "foo", atom_new_int(42));
- struct list *result = eval_str_env("foo", env);
+ struct atom *result = eval_str("foo", env);
ASSERT_TRUE(result != NULL);
ASSERT_EQ(ATOM_INT, ATOM_TYPE(result));
- ASSERT_EQ(42, LIST_GET_ATOM(result)->l);
+ ASSERT_EQ(42, result->l);
}
TEST(evaluate_missing_symbol)
{
- struct list *env = env_new();
+ struct env *env = env_new();
- struct list *result = eval_str_env("foo", env);
+ struct atom *result = eval_str("foo", env);
ASSERT_TRUE(result != NULL);
ASSERT_EQ(ATOM_NIL, ATOM_TYPE(result));
@@ -348,9 +322,9 @@ TEST(evaluate_missing_symbol)
TEST(define)
{
- struct list *env = env_new();
+ struct env *env = env_new();
- struct list *result = eval_str_env("(define x 100)", env);
+ struct atom *result = eval_str("(define x 100)", env);
ASSERT_TRUE(result != NULL);
@@ -363,9 +337,9 @@ TEST(define)
TEST(define_missing_value)
{
- struct list *env = env_new();
+ struct env *env = env_new();
- struct list *result = eval_str_env("(define x)", env);
+ struct atom *result = eval_str("(define x)", env);
ASSERT_TRUE(result != NULL);
ASSERT_EQ(ATOM_NIL, ATOM_TYPE(result));
@@ -375,18 +349,18 @@ TEST(define_missing_value)
TEST(define_nonsymbol_as_name)
{
- struct list *env = env_new();
+ struct env *env = env_new();
- struct list *result = eval_str_env("(define 1 100)", env);
+ struct atom *result = eval_str("(define 1 100)", env);
ASSERT_TRUE(result != NULL);
ASSERT_EQ(ATOM_NIL, ATOM_TYPE(result));
}
TEST(define_with_val_as_expr)
{
- struct list *env = env_new();
+ struct env *env = env_new();
- struct list *result = eval_str_env("(define x (* 3 3))", env);
+ struct atom *result = eval_str("(define x (* 3 3))", env);
ASSERT_TRUE(result != NULL);
@@ -397,5 +371,4 @@ TEST(define_with_val_as_expr)
ASSERT_EQ(9, atom->l);
}
-
#endif /* BUILD_TEST */
generated by cgit v1.2.3 (git 2.25.1) at 2025-12-15 04:34:16 +0000