Add defun without evaluation

src/special.c

@@ -0,0 +1,86 @@
+#include "state.h"
+#include "lisp.h"
+#include "utility.h"
+#include "internal.h"
+
+#include <assert.h>
+
+struct ucl_object *ucl_special_let(struct ucl_state *state, struct ucl_object *args) {
+    // TODO: Check arguments
+    struct ucl_object *assignments = ucl_car(args);
+    struct ucl_object *expressions = ucl_cdr(args);
+    struct ucl_state *let_state = ucl_state_create_child(state);
+
+    FOREACH_LIST(assignments, iter, item) {
+        // TODO: Check arguments
+        struct ucl_object *sym = ucl_car(item);
+        struct ucl_object *expr = ucl_car(ucl_cdr(item));
+        struct ucl_object *value = ucl_evaluate(let_state, expr);
+
+        assert(sym->type == UCL_TYPE_SYMBOL);
+        //assert(ucl_list_length(expr)->integer == 1);
+
+        if (value->type == UCL_TYPE_ERROR) {
+            // TODO cleanup
+            return value;
+        }
+        ucl_state_put(let_state, sym->symbol, value);
+    }
+
+    struct ucl_object *result = NULL;
+    FOREACH_LIST(expressions, iter, item) {
+        result = ucl_evaluate(let_state, item);
+        if (result->type == UCL_TYPE_ERROR) {
+            return result;
+        }
+    }
+
+
+    ucl_state_delete(let_state);
+    return result;
+}
+
+struct ucl_object *ucl_special_if(struct ucl_state *state, struct ucl_object *args) {
+    // TODO: Check arguments
+    struct ucl_object *cond = ucl_car(args);
+    struct ucl_object *true_form = ucl_list_nth(args, 1);
+    struct ucl_object *false_forms = ucl_cdr(ucl_cdr(args));
+
+    struct ucl_object *cond_result = ucl_evaluate(state, cond);
+    UCL_RET_IF_ERROR(cond_result);
+    if (ucl_truthy(cond_result)->type == UCL_TYPE_SYMBOL) {
+        return ucl_evaluate(state, true_form);
+    }
+
+    struct ucl_object *result = NULL;
+
+    FOREACH_LIST(false_forms, iter, form) {
+        result = ucl_evaluate(state, form);
+    }
+
+    return (result == NULL) ? ucl_nil_create() : result;
+}
+
+
+struct ucl_object *ucl_special_defun(struct ucl_state *state, struct ucl_object *args) {
+   // TODO: Check arguments
+    struct ucl_object *fun_sym = ucl_car(args);
+    if (fun_sym->type != UCL_TYPE_SYMBOL) {
+        return ucl_error_create("First argument to defun must be a symbol");
+    }
+
+    struct ucl_object *fun_args = ucl_list_nth(args, 1);
+    if (fun_args->type != UCL_TYPE_CELL) {
+        // TODO: Check that the list contains only symbols
+        return ucl_error_create("Second argument to defun must be a list of symbols");
+    }
+
+    // For now, other elements are just forms to be evaluated. Maybe one day
+    // there will be docstrings, maybe not!
+
+    // Functions are added to the root scope
+    ucl_state_put(ucl_state_get_root(state), fun_sym->symbol, ucl_cdr(args));
+
+    return fun_sym;
+
+}