`null` is now a real pointer literal and null-tests are comparisons, instead of
`ptr_null()` and `ptr_is_null(x)`:
ptr_null() -> null
ptr_is_null(x) -> (x == null)
not ptr_is_null(x) -> (x != null)
Mechanics: a new E_NULL primary (`null`, like true/false) lowers to the `null`
pointer; emit_bin's comparison path now picks `ptr` vs `i32` from operand type
(via llty), so `==`/`!=` work on any pointer/record/slice. The two intrinsics are
deleted.
Two reseeds: (A) add the literal + ptr comparison keeping the intrinsics; (B)
migrate all 182 call sites (compiler + runtime, via a balanced-paren script that
skips string-literal args and rewrites `not ptr_is_null` to `!= null`) and delete
the intrinsics. Node/Val/Buf/Tok field defaults now read `ptr = null`.
Vocabulary drops the two from LUDIC_INTRINSICS; `null` joins true/false as a
language constant (grammar + ludic_syntax.h). LANGUAGE.md notes the literal.
Reseeded (21664 lines); C-free fixpoint holds; goldens identical; 17/17; vocab +
doc-fences clean.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Orkuncakilkaya
70ab79a4e9