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diff --git a/docs/history/15-o3/code/examples/selfpatch.zc b/docs/history/15-o3/code/examples/selfpatch.zc
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+// code is data: find the literal 'A' inside f's compiled words and rewrite it.
+// on the jit the store lands on translated code, which gets dropped and
+// retranslated on the next call.
+fn f() { putc('A'); return 0; }
+fn litw(v) { return v + v + 1; }	// how the vm encodes a literal push
+fn main()
+{
+	let p = f;
+	f();
+	while (*p != litw('A')) p++;
+	*p = litw('B');
+	f();
+	*p = litw('C');
+	f();
+	putc(10);
+	return 0;
+}