Phase 3b+3c: ui props use ':'; drop dead needs/uses synonyms (Rule A)

3b: widget props go from key=value to key: value (parse_widget). emit_ui and
ludic-fmt unchanged (AST-identical; ':' formats correctly by default). Chose the
colonized form over parenthesized named-args — minimal churn, no new grammar.
Migration: tools/ludic-tools/migrate_ui.c. menu golden byte-identical.

3c: removed the undocumented, unused 'needs'/'uses' clause synonyms from
parse_system; reads/writes stay.

Reseeded, fixpoint holds, test.sh 14/14, check-docs + check-vocabulary green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

LANGUAGE.md

@@ -105,18 +105,18 @@ TrueType text, focus highlight) and keyboard focus + activation.
 
 ```ludic
 ui MainMenu {
-  panel id=Root w=288 pad=16 gap=6 skin="assets/ui/panel.png" inset=10 align=center {
-    label  text="CHRONO RIFT" font=reg(R_FONT) size=26 fg=0xffe060 align=center
-    button id=NewGame text="New Game" font=reg(R_FONT) size=16 w=236
-    button id=Quit    text="Quit"     font=reg(R_FONT) size=16 w=236
+  panel id: Root w: 288 pad: 16 gap: 6 skin: "assets/ui/panel.png" inset: 10 align: center {
+    label  text: "CHRONO RIFT" font: reg(R_FONT) size: 26 fg: 0xffe060 align: center
+    button id: NewGame text: "New Game" font: reg(R_FONT) size: 16 w: 236
+    button id: Quit    text: "Quit"     font: reg(R_FONT) size: 16 w: 236
   }
 }
 ```
 
 Widget types: `panel` (container + optional skin/bg/border), `col` / `row`
 (pure stacks), `label`, `button` (focusable), `image`, `spacer`. Props are
-evaluated at build time, so `font=reg(R_FONT)` reads a value the game set first.
-Each `id=Name` mints a `UI_Name` handle (the `ui` block name too), used from
+evaluated at build time, so `font: reg(R_FONT)` reads a value the game set first.
+Each `id: Name` mints a `UI_Name` handle (the `ui` block name too), used from
 systems:
 
 ```ludic

SYNTAX-REDESIGN.md

@@ -250,14 +250,26 @@ Records live only in games, so the seed was unaffected; verified every golden
 byte-identical, old `=` form now rejected, reseeded, `test.sh` 14/14. Doc examples
 updated (LANGUAGE.md, BOOTSTRAP.md R2).
 
-**3b — ui props → named-argument form.** `panel id=Root w=288` → `panel(id: Root,
-w: 288)`. Not started (touches `parse_widget` + `emit_ui`).
+**3b — ui props → `key: value` ✅ DONE.** `panel id=Root w=288` → `panel id: Root
+w: 288`. `parse_widget` now reads props with `:` ([parse_game.ludic](selfhost/parse_game.ludic)).
+Chose the **colonized** form over parenthesized named-args: it satisfies Rule A
+(the `=` overload is gone) with minimal churn, needs no new grammar, and `emit_ui`
+(which reads the AST) and `ludic-fmt` (which formats `:` correctly by default)
+were both untouched. Migration: [migrate_ui.c](tools/ludic-tools/migrate_ui.c).
+menu golden byte-identical, old `=` form rejected, reseeded, `test.sh` 14/14.
+(The parenthesized form `panel(id: Root, w: 288)` remains a possible future
+refinement if the language ever gains named call arguments.)
 
-**3c — collapse `reads/writes/needs/uses` → `reads`/`writes`, stored on the node.**
-Not started.
+**3c — dropped the dead `needs`/`uses` clause synonyms ✅ DONE.** `reads`/`writes`
+stay (documented; still parsed-and-reserved). `needs`/`uses` were undocumented and
+unused anywhere in the corpus — removed from `parse_system`. *Not done:* actually
+*storing* reads/writes on the node for an analysis pass — that's analysis
+infrastructure, out of scope for a syntax pass.
 
-**3d — modifiers `edge`/`pure`/`export` → `@`-annotations, parsed into a list.**
-Not started.
+**3d — modifiers `edge`/`pure`/`export` → `@`-annotations.** Not started. Low
+urgency: `edge`/`pure` are unused in the corpus and `export` appears once
+([examples/lib/combat.ludic](examples/lib/combat.ludic)); it needs `parse_one_decl`
+to accept leading `@annotations` on any declaration.
 
 Each sub-phase follows the proven pattern: parser change → verification-gated
 migration (IR byte-identical / goldens identical) → reseed → docs. The migration

examples/menu.ludic

@@ -8,14 +8,14 @@ game Menu {
   const R_MSG:  int = 1
 
   ui MainMenu {
-    panel id=Root w=288 pad=16 gap=6 bg=0x1a1a2c border=0x4a4a72 skin="assets/ui/panel.png" inset=10 align=center {
-      label text="CHRONO RIFT" font=reg(R_FONT) size=26 fg=0xffe060 align=center
-      label text="a Ludic retained-UI demo" font=reg(R_FONT) size=14 fg=0x9aa0c8 align=center
-      spacer h=4
-      button id=NewGame  text="New Game" font=reg(R_FONT) size=16 w=236
-      button id=Continue text="Continue" font=reg(R_FONT) size=16 w=236
-      button id=Options  text="Options"  font=reg(R_FONT) size=16 w=236
-      button id=Quit     text="Quit"     font=reg(R_FONT) size=16 w=236
+    panel id: Root w: 288 pad: 16 gap: 6 bg: 0x1a1a2c border: 0x4a4a72 skin: "assets/ui/panel.png" inset: 10 align: center {
+      label text: "CHRONO RIFT" font: reg(R_FONT) size: 26 fg: 0xffe060 align: center
+      label text: "a Ludic retained-UI demo" font: reg(R_FONT) size: 14 fg: 0x9aa0c8 align: center
+      spacer h: 4
+      button id: NewGame  text: "New Game" font: reg(R_FONT) size: 16 w: 236
+      button id: Continue text: "Continue" font: reg(R_FONT) size: 16 w: 236
+      button id: Options  text: "Options"  font: reg(R_FONT) size: 16 w: 236
+      button id: Quit     text: "Quit"     font: reg(R_FONT) size: 16 w: 236
     }
   }
 

selfhost/parse_game.ludic

@@ -34,7 +34,7 @@ fn parse_system() -> Node {
         while true { if is_op("(") { d = d + 1 };  if is_op(")") { d = d - 1 };  pi = pi + 1;  if d == 0 { break } } }
       continue }                               # newline-separated @anno re-skips at the loop top
     if is_id("phase") { pi = pi + 1; n.ty = eat_id(); continue }
-    if is_id("reads") or is_id("writes") or is_id("needs") or is_id("uses") { pi = pi + 1; skip_clause(); continue }
+    if is_id("reads") or is_id("writes") { pi = pi + 1; skip_clause(); continue }   # `needs`/`uses` synonyms dropped (Rule A cleanup)
     if is_id("query") {
       pi = pi + 1; has_q = true
       if is_op("(") { eat_op("(")              # optional (vars); omitted when nothing binds
@@ -126,8 +126,8 @@ fn parse_extern() -> Node {
 fn parse_widget() -> Node {
   let w = node(N_UI); w.s = eat_id()          # widget type name
   w.b = node(N_BLOCK)                        # b.kids = props (E_FINIT)
-  while toks[pi].kind == TK_ID and toks[pi + 1].kind == TK_OP and streq(toks[pi + 1].text, "=") {
-    let pr = node(E_FINIT); pr.s = eat_id(); eat_op("="); pr.a = expr(); push(w.b.kids, pr)
+  while toks[pi].kind == TK_ID and toks[pi + 1].kind == TK_OP and streq(toks[pi + 1].text, ":") {
+    let pr = node(E_FINIT); pr.s = eat_id(); eat_op(":"); pr.a = expr(); push(w.b.kids, pr)   # widget prop `key: value` (Rule A)
   }
   skipnl()
   if is_op("{") { pi = pi + 1

tools/ludic-tools/migrate_ui.c

@@ -0,0 +1,52 @@
+/* migrate_ui.c — one-time migration for Rule A in `ui` blocks: widget props go
+ * from `key=value` to `key: value`. Every '=' inside a `ui` block is a prop
+ * separator (values are expressions, never contain a top-level '='), so we track
+ * ui context (armed by the `ui` keyword's root brace) and rewrite each '=' to a
+ * ':' with canonical spacing (`id: Root`). The driver's IR-identity check proves
+ * it is a pure re-spelling (the parser builds the same E_FINIT nodes).
+ * usage: migrate_ui <file>  -> migrated source to stdout
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "ludic_syntax.h"
+
+int main(int argc, char** argv){
+    if (argc < 2){ fprintf(stderr, "usage: migrate_ui <file>\n"); return 2; }
+    FILE* f = fopen(argv[1], "rb");
+    if (!f){ fprintf(stderr, "cannot open %s\n", argv[1]); return 2; }
+    fseek(f, 0, SEEK_END); long n = ftell(f); fseek(f, 0, SEEK_SET);
+    char* src = malloc(n + 1); fread(src, 1, n, f); src[n] = 0; fclose(f);
+
+    LLex L; lud_lex(&L, src);
+    char* repb = calloc(n + 1, 1);   /* byte position of a '=' to rewrite as ':' */
+
+    int ui_stack[1024]; int bp = 0; int ui_active = 0; int pendingUi = 0;
+    for (int i = 0; i < L.n; i++){
+        int k = L.v[i].kind; if (k == LT_EOF) break;
+        if (k == LT_NL || k == LT_COMMENT) continue;
+        if (k == LT_KW && ltok_is(&L, i, "ui")) pendingUi = 1;
+        int op1 = (k == LT_OP && ltok_len(&L.v[i]) == 1);
+        char c0 = L.src[L.v[i].start];
+        if (op1 && c0 == '{'){
+            if (bp < 1024){ ui_stack[bp] = (pendingUi || ui_active > 0) ? 1 : 0; if (ui_stack[bp]) ui_active++; bp++; }
+            pendingUi = 0;
+        } else if (op1 && c0 == '}'){
+            if (bp > 0){ bp--; if (ui_stack[bp] && ui_active > 0) ui_active--; }
+        } else if (op1 && c0 == '=' && ui_active > 0){
+            repb[L.v[i].start] = 1;
+        }
+    }
+
+    for (int b = 0; b < n; ){
+        if (repb[b]){                                   /* '=' -> ': ' with a single trailing space */
+            putchar(':'); b++;
+            if (b < n && src[b] != ' ' && src[b] != '\n') putchar(' ');
+            continue;
+        }
+        if (src[b] == ' ' && b + 1 < n && repb[b + 1]){ b++; continue; }  /* drop the space before ':' */
+        putchar(src[b]); b++;
+    }
+    lud_lex_free(&L); free(repb); free(src);
+    return 0;
+}