Run the break loop rather than quote it, since the restart order is a claim

NEXT.md prints the banner with the restarts in source order; the walk is
innermost-first, so it is the other way round. A --dev build under timeout is
enough to settle that, and settles the two place and global snippets with it.

web/examples/breakdemo.flan

@@ -0,0 +1,15 @@
+(import agent "vendor:agent")
+
+(defstruct Missing [id i32])
+
+(defn load [n i32] i32
+  (restart-case
+    (do (error (Missing {:id n}))
+        0)
+    (use-placeholder [] -1)
+    (retry           [] 7)))
+
+(defn main []
+  (agent/start "/tmp/flan-breakdemo.sock")
+  (print-i64 (i64 (load 1)))
+  (newline))

web/examples/breakdemo.out

@@ -0,0 +1,4 @@
+
+flan: unhandled Missing — stopped, not dead.
+  restart: retry
+  restart: use-placeholder

web/examples/check.sh

@@ -10,28 +10,49 @@
 here=$(cd "$(dirname "$0")" && pwd)
 root=$(cd "$here/../.." && pwd)
 FLAN=${FLAN:-$root/_build/default/bin/main.exe}
+tmp=${TMPDIR:-/tmp}/flan-web-check.$$
 
 cd "$here" || exit 1
 fail=0
+ok()   { echo "ok    $1"; }
+bad()  { echo "FAIL  $1"; fail=1; }
+
 for f in *.flan; do
-  # shimdemo.flan calls raylib, so it is not run. What it demonstrates is the
-  # C the compiler writes, which is checked below by generating that instead.
-  [ "$f" = shimdemo.flan ] && continue
+  # Two programs are not run by `flan run`; each is checked its own way below.
+  [ "$f" = shimdemo.flan ] && continue    # calls raylib
+  [ "$f" = breakdemo.flan ] && continue   # stops and waits, on purpose
   got=$( { "$FLAN" run "$f"; echo "exit $?"; } 2>&1 )
-  if [ "$got" = "$(cat "${f%.flan}.out")" ]; then
-    echo "ok    $f"
-  else
-    echo "FAIL  $f"
+  if [ "$got" = "$(cat "${f%.flan}.out")" ]; then ok "$f"; else
+    bad "$f"
     printf '%s\n' "$got" | diff -u "${f%.flan}.out" - || true
-    fail=1
   fi
 done
 
+# shimdemo.flan is the declare-c example: what it demonstrates is the C the
+# compiler writes, so it is checked by generating that rather than by running.
 if "$FLAN" shim shimdemo.flan | grep -q 'GetMousePosition(void)'; then
-  echo "ok    shimdemo.flan (flan shim)"
+  ok "shimdemo.flan (flan shim)"
 else
-  echo "FAIL  shimdemo.flan (flan shim)"
-  fail=1
+  bad "shimdemo.flan (flan shim)"
+fi
+
+# breakdemo.flan is the break loop: an unhandled error stops the program and
+# waits for someone to pick a restart, so it never exits on its own. It needs
+# a --dev build (the hook lives in vendor/agent) and it is killed after a few
+# seconds; what is checked is the banner it printed before it stopped.
+if command -v timeout >/dev/null 2>&1; then
+  if "$FLAN" build breakdemo.flan --dev -o "$tmp" >/dev/null 2>&1; then
+    got=$(timeout 5 "$tmp" 2>&1)
+    rm -f "$tmp"
+    if [ "$got" = "$(cat breakdemo.out)" ]; then ok "breakdemo.flan (break loop)"; else
+      bad "breakdemo.flan (break loop)"
+      printf '%s\n' "$got" | diff -u breakdemo.out - || true
+    fi
+  else
+    bad "breakdemo.flan (build --dev)"
+  fi
+else
+  echo "skip  breakdemo.flan (no timeout(1))"
 fi
 
 exit $fail

web/examples/geom/len.flan

@@ -1,4 +1,4 @@
-;; A second file in the same directory shares one top-level scope: it does not
-;; import vec.flan, and the order of the two files does not matter.
+;; geom/len.flan — a second file in the same directory shares one top-level
+;; scope: it does not import vec.flan, and the order of the two does not matter.
 (defn length [v V2] f32
   (sqrt-f32 (+ (* (.x v) (.x v)) (* (.y v) (.y v)))))

web/examples/geom/vec.flan

@@ -1,4 +1,4 @@
-;; No package declaration: the name comes from the directory.
+;; geom/vec.flan — no package declaration: the name comes from the directory.
 (defstruct V2 [x f32  y f32])
 
 (defn add [a V2  b V2] V2

web/examples/globals.flan

@@ -0,0 +1,12 @@
+(defconst cell-size 5)                 ; a compile-time constant
+(defconst gravity f32 0.05)            ; with its type named
+(defvar current-color i32)             ; zeroed storage
+(defconst rows 3)
+(defconst cols 4)
+(defvar grid [rows [cols u32]])        ; BSS, rows*cols*4 bytes
+
+(defn main []
+  (print-i64 (i64 cell-size)) (newline)
+  (print-f64 (f64 gravity)) (newline)
+  (print-i64 (i64 current-color)) (newline)
+  (print-i64 (i64 (at grid 2 3))) (newline))

web/examples/globals.out

@@ -0,0 +1,5 @@
+5
+0.05
+0
+0
+exit 0

web/examples/pkg.flan

@@ -1,4 +1,5 @@
-;; The directory is the package. Everything it declares arrives qualified.
+;; pkg.flan — the directory is the package, and everything it declares
+;; arrives qualified by the alias this import chose.
 (import g "geom")
 
 (defn main []

web/examples/places.flan

@@ -0,0 +1,20 @@
+(defstruct Enemy [hp i32  name string])
+
+(defvar spawned i32)
+(defconst room-size 4)
+(defvar room [room-size i32])
+
+;; `set` takes a fixed list of forms, not an extensible setf.
+(defn main []
+  (let [e (Enemy {:hp 10 :name "slime"})
+        p (addr e)]
+    (set spawned (+ spawned 1))    ; a local or a defvar
+    (set (.hp e) 7)                ; a struct field
+    (set (.hp p) 8)                ; through a (Ptr Enemy) — derefs one level
+    (set (at room 2) 5)            ; a fixed array or slice element
+    (set (deref p) (Enemy {:hp 3 :name "wisp"}))   ; a whole-object store
+
+    (print-i64 (i64 (.hp e))) (newline)
+    (print-line (.name e))
+    (print-i64 (i64 (at room 2))) (newline)
+    (print-i64 (i64 spawned)) (newline)))

web/examples/places.out

@@ -0,0 +1,5 @@
+3
+wisp
+5
+1
+exit 0