content: relative block reorder (move.sx) + 11 tests (668/668)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-07 05:04:45 +00:00
parent c0ca2509d0
commit 715dbe248f
6 changed files with 146 additions and 5 deletions
--- a/lib/content/move.sx
+++ b/lib/content/move.sx
@@ -0,0 +1,69 @@
+;; content-on-sx — relative block reorder.
+;;
+;; Move a top-level block to just before / after another block by id — more
+;; ergonomic than the index-based doc-move. No-op if either id is missing.
+;; Immutable; composes the doc.sx list helpers.
+;;
+;; Requires (loaded by harness): doc.sx.
+
+(define
+  content/move-before
+  (fn
+    (doc id target)
+    (let
+      ((blk (doc-find doc id)))
+      (if
+        (= blk nil)
+        doc
+        (let
+          ((without (ct-remove-id (doc-blocks doc) id)))
+          (let
+            ((idx (ct-index-of without target)))
+            (if
+              (= idx -1)
+              doc
+              (doc-with-blocks doc (ct-insert-at without idx blk)))))))))
+
+(define
+  content/move-after
+  (fn
+    (doc id target)
+    (let
+      ((blk (doc-find doc id)))
+      (if
+        (= blk nil)
+        doc
+        (let
+          ((without (ct-remove-id (doc-blocks doc) id)))
+          (let
+            ((idx (ct-index-of without target)))
+            (if
+              (= idx -1)
+              doc
+              (doc-with-blocks
+                doc
+                (ct-insert-at without (+ idx 1) blk)))))))))
+
+(define
+  content/move-to-front
+  (fn
+    (doc id)
+    (let
+      ((blk (doc-find doc id)))
+      (if
+        (= blk nil)
+        doc
+        (doc-with-blocks doc (cons blk (ct-remove-id (doc-blocks doc) id)))))))
+
+(define
+  content/move-to-back
+  (fn
+    (doc id)
+    (let
+      ((blk (doc-find doc id)))
+      (if
+        (= blk nil)
+        doc
+        (doc-with-blocks
+          doc
+          (append (ct-remove-id (doc-blocks doc) id) (list blk)))))))