From 02736718dc2e78f61ef84e44006c0d0c6b4058cf Mon Sep 17 00:00:00 2001
From: Alexander Rosenberg <zanderpkg@pm.me>
Date: Wed, 24 Sep 2025 05:24:33 -0700
Subject: [PATCH] A buch of sequence functions

---
 src/kernel.sl | 37 +++++++++++++++++++++++++++++++++++++
 src/lisp.c    | 12 ++++++++++++
 src/lisp.h    |  1 +
 3 files changed, 50 insertions(+)

diff --git a/src/kernel.sl b/src/kernel.sl
index c2b6116..3ada365 100644
--- a/src/kernel.sl
+++ b/src/kernel.sl
@@ -399,3 +399,40 @@
     (when (zerop n)
       (return-from nthtail tail))
     (setq n (- n 1))))
+
+(defmacro doindex (vars &rest body)
+  (let ((i '::i))
+    (list 'let (list (list i 0))
+          (list 'while (list '< i (list 'length (second vars)))
+                (apply 'list 'let (list (list (first vars) i))
+                      body)
+                (list 'setq i (list '+ i 1))))))
+
+(defmacro dovector (vars &rest body)
+  (let ((vec '::vec)
+        (i '::i)
+        (vh (head vars)))
+    (list 'let (list (list vec (second vars)))
+          (list 'doindex (list i vec)
+                (if (symbolp vh)
+                    (apply 'list 'let (list (list vh (list 'aref vec i)))
+                           body)
+                  (apply 'list 'let (list (list (first vh) i)
+                                          (list (second vh) (list 'aref vec i)))
+                         body))))))
+
+(defun foreach (func seq)
+  (tcase seq
+         (hash-table (maphash func seq))
+         (list
+          (dolist (elt seq)
+            (funcall func elt)))
+         ((or vector string)
+          (dovector (elt seq)
+            (funcall func elt)))))
+
+(defun code-char (code)
+  (string [code]))
+
+(defun char-code (str)
+  (aref str 0))
diff --git a/src/lisp.c b/src/lisp.c
index 251d0e9..56f626e 100644
--- a/src/lisp.c
+++ b/src/lisp.c
@@ -2443,6 +2443,17 @@ DEFUN(hash_table_count, "hash-table-count", (LispVal * table)) {
     return make_lisp_integer(((LispHashtable *) table)->count);
 }
 
+DEFUN(maphash, "maphash", (LispVal * func, LispVal *table)) {
+    HT_FOREACH_VALID_INDEX(table, i) {
+        LispVal *args =
+            const_list(true, 2, HASH_KEY(table, i), HASH_VALUE(table, i));
+        WITH_CLEANUP(args, {
+            refcount_unref(Ffuncall(func, args)); //
+        });
+    }
+    return Qnil;
+}
+
 DEFUN(puthash, "puthash", (LispVal * table, LispVal *key, LispVal *value)) {
     return refcount_ref(puthash(table, key, value));
 }
@@ -3522,4 +3533,5 @@ static void register_symbols_and_functions(void) {
     REGISTER_FUNCTION(string, "(val)", "");
     REGISTER_FUNCTION(subvector, "(seq &opt start end)", "");
     REGISTER_FUNCTION(string_to_vector, "(str)", "");
+    REGISTER_FUNCTION(maphash, "(func table)", "");
 }
diff --git a/src/lisp.h b/src/lisp.h
index 3ecbbbb..66c2cdf 100644
--- a/src/lisp.h
+++ b/src/lisp.h
@@ -516,6 +516,7 @@ DECLARE_FUNCTION(hash_table_p, (LispVal * val));
 DECLARE_FUNCTION(make_hash_table, (LispVal * hash_fn, LispVal *eq_fn));
 DECLARE_FUNCTION(copy_hash_table, (LispVal * table));
 DECLARE_FUNCTION(hash_table_count, (LispVal * table));
+DECLARE_FUNCTION(maphash, (LispVal * func, LispVal *table));
 DECLARE_FUNCTION(puthash, (LispVal * table, LispVal *key, LispVal *value));
 DECLARE_FUNCTION(gethash, (LispVal * table, LispVal *key, LispVal *def));
 DECLARE_FUNCTION(remhash, (LispVal * table, LispVal *key));