Brummel
4ec8f90b19
Third tranche, completing the honesty-rule sweep across the remaining
contracts. Same conservative bar: cut unbacked-verification claims,
change/deletion history, and forward-intent; keep present-state design
rationale.
- 0003: drop "sanitiser-verified" — no TSan/sanitiser test exists in
the tree, so the claim asserts a verification that does not happen.
The data-race-freedom property (argued from the non-atomic-but-never-
shared hot path + atomic-relaxed shared counter) stays.
- 0008: the `Type::Con.name` hash paragraph ("the tightening shifted
the hashes ... The new pins ... re-asserts the pre-tightening hashes")
-> present-state: which fixtures carry which hash shape and which test
pins each.
- 0013: drop "the former codegen-side fallback (at ..., and the
now-deleted `synth_with_extras`) is retracted" (deletion history; the
present fact is that codegen does not re-resolve, per the boundary);
"A future refactor that loosens any one of the four breaks ..." ->
present-tense statement that the four are load-bearing and each pinned.
- 0017: drop "a real cost surfaced by the `bench_closure_chain`
regression at the operator-routing-eq-ord milestone" (history) and
"the symmetric extensions are mechanical when the first such workload
appears" (forward-intent); keep the present-state allocation cost, the
pin, and the Int-only-asymmetry rationale.
All 18 contracts now reviewed against the code. Ledger pins green;
honesty sweep clean.
3.9 KiB
Prelude (built-in) classes
Prelude (built-in) classes
The prelude ships the Ordering ADT, the Eq and Ord
classes, primitive Eq Int/Bool/Str/Unit and
Ord Int/Bool/Str instances, and the five polymorphic free-fn
helpers ne/lt/le/gt/ge. The primitive Eq / Ord
instance bodies carry the (intrinsic) marker in examples/prelude.ail
(the marker is the lockstep partner to the INTERCEPTS registry);
the codegen intercept try_emit_primitive_instance_body supplies
their single-instruction bodies (icmp eq i64 for eq__Int,
icmp eq i1 for eq__Bool, @ail_str_eq for eq__Str,
ret i1 1 for eq__Unit; a three-way icmp ladder constructing
LT/EQ/GT for compare__T) and attaches alwaysinline so
the call folds to the single instruction at every use site.
The five Ord-class free helpers (ne/lt/le/gt/ge) have
source-level bodies that route through eq / compare plus
match over Ordering — written that way so the surface form is
LLM-natural and so user-ADT instances of Eq/Ord automatically
pick up working helpers without any per-type opt-in. At Int the
codegen intercept short-circuits this indirection: lt__Int,
le__Int, gt__Int, ge__Int, and ne__Int are intercept-
overridden to emit icmp slt i64 / sle i64 / sgt i64 /
sge i64 / ne i64 directly, bypassing the compare__Int →
Ordering-ctor → match path. Without this short-circuit the
Ordering ctor allocates per call inside hot loops; the
short-circuit is pinned by
crates/ail/tests/ord_int_intercept_ir_pin.rs. It
is Int-only by deliberate asymmetry: no current bench or
example fixture exercises Ord-lt/le/gt/ge at Bool or
Str at sufficient call frequency to justify the intercept-arm
maintenance.
Float has neither Eq nor Ord instance per Float semantics; a polymorphic helper invoked at Float fires
NoInstance at typecheck with a Float-aware diagnostic that names
the explicit float_eq / float_lt alternatives and
cross-references this section. The lookup machinery that turns a
show x call site into the right monomorphic instance is
documented in method dispatch.
Float comparison is a separate surface: the six monomorphic prelude
fns float_eq / float_ne / float_lt / float_le / float_gt
/ float_ge each carry the type (Float, Float) -> Bool without
a class constraint. They lower via the same intercept machinery as
the primitive Eq instances (single fcmp instruction with the
matching predicate oeq / une / olt / ole / ogt / oge,
plus alwaysinline). They replace what would otherwise be a
polymorphic == / < on Float — Float gets full comparability
via explicit named fns, not via an implicit class instance.
The prelude ships class Show a where show : (a borrow) -> Str and
primitive Show Int, Show Bool, Show Str, Show Float
instances. Float is included in Show (unlike Eq/Ord) — IEEE-754
makes structural equality and total ordering semantically dubious,
but textual representation of a Float is well-defined modulo the
NaN-spelling caveat in Float semantics. Each
Show <T> instance body is a single-application lambda invoking the
corresponding runtime primitive (int_to_str, bool_to_str,
str_clone, float_to_str; see Str ABI for the
heap-Str primitives); no codegen intercept is required. The
polymorphic helper print : forall a. Show a => a -> () !IO has body
\x -> let s = show x in do io/print_str s (explicit let-binder for
heap-Str RC discipline per the Str carve-out in
Str ABI). The let-binder is
structurally pinned by crates/ail/tests/print_mono_body_shape.rs.
Routing through print is the path for non-Str primitives;
io/print_str is the only built-in direct-output effect-op.
Ratified by: crates/ail/tests/show_no_instance_e2e.rs.