richer formatting

LANGUAGE.md

@@ -150,12 +150,13 @@ as `math.divfloor(a, b)` resolve to ordinary functions.
 - demand-monomorphized Brolang and C-ABI functions
 - integer comptime value parameters such as `make_array func($N usize) [N]u8`, specialized by value and omitted from the runtime ABI
 - explicit comptime type parameters such as `max func($T type, a, b T) T`, specialized by type and omitted from the runtime ABI
-- comptime type/integer/string parameters may appear anywhere, are erased from the runtime ABI, and may be omitted when uniquely recoverable from runtime arguments or the immediate expected result; `_` is an explicit inference hole
+- comptime parameters may appear anywhere, are erased from the runtime ABI, and accept recursively stable booleans, integers, floats, types, immutable bytes, enums, fixed arrays, records/tuples, optionals, and tagged unions; equal structural values share specializations, while pointers, functions, general slices, fallibles, ranges, untagged unions, and undefined values have no stable comptime identity
+- comptime parameters may be omitted when uniquely recoverable from runtime arguments, the immediate expected result, or exact type-factory provenance; `_` is an explicit inference hole
 - forced typed comptime expressions such as `$sum(1, 2)`, `$Point { x = 1, y = 2 }`, and comptime value blocks such as `${ yield 4 }`
 - comptime execution for bodyful Brolang functions with mutable locals, loops, `defer`, `match`, `try`/`catch`, pointer/slice storage mutation, pointer captures, and calls through comptime-known function values; `undefined` storage may be initialized at comptime, but remaining poison cannot be observed
 - comptime type factories such as `Box func($T type) type { return struct { value T } }`; calls like `Box(i32)` are concrete nominal types and may appear anywhere a type is expected
 - tuple types are unnamed-field structs (`struct { i32, []u8 }`), tuple values use `{1, "bro"}` / `{1,}` / `{}`, and fields use canonical numeric names such as `.0`
-- `typeinfo!`, `field!`, `compile_error!`, and semantic `inline for` provide compile-time record reflection and heterogeneous static expansion without runtime metadata; reflected aggregates remain persistent compile-time values, and inline-loop `break` / `continue` must be selected entirely at comptime
+- `typeinfo!`, `field!`, `compile_error!`, and semantic `inline for` provide compile-time record and enum reflection and heterogeneous static expansion without runtime metadata; enum reflection exposes declaration-ordered fields, reflected aggregates remain persistent compile-time values, and inline-loop `break` / `continue` must be selected entirely at comptime
 - bodyful `c_func` definitions and bodyless `c_func` declarations with exact external symbol names
 - concrete-only C signatures, C variadic declarations/calls, and C default argument promotions
 - native function pointer values and types with `@func(...) R`, fallible `@func(...) R ! E`, optional `?@func(...) R`, and non-variadic native indirect calls
@@ -174,7 +175,7 @@ as `math.divfloor(a, b)` resolve to ordinary functions.
 - root `std` re-exports `ArrayList(T)` while its operations remain in `std/arraylist`
 - `std/mem` generic slice equality, allocator contract with raw byte operations, typed `empty` / `alloc` / `realloc` / `free`, overflow checks, zero-sized-type support, and failure-preserving reallocation
 - `std/arraylist` generic `ArrayList(T)` with direct `items` slice access, explicit capacity, allocator ownership, fallible reserve/append, clear, and deinit
-- `std/io` explicit `Io` capabilities, `Reader`/`Writer` stream values, allocation-free `write_all`, and comptime-expanded writer-first `print`; formatting currently supports sequential `{s}` / `{d}` plus `{{` / `}}`, with malformed formats and incompatible tuple fields rejected at comptime
+- `std/io` explicit `Io` capabilities, `Reader`/`Writer` stream values, allocation-free `write_all`, and comptime-expanded writer-first `print`; formatting supports natural `{}`, byte `{s}`, decimal `{d}`, integer `{b}` / `{o}` / `{x}` / `{X}`, byte-character `{c}`, scientific float `{e}`, and `{{` / `}}`, with malformed formats and incompatible tuple fields rejected at comptime
 - entry points are either `main func() ...` or `main func(init process.Init) ...`; `std/process.Init` carries startup capabilities, currently only `io`, while the system provider remains hidden inside `std/io`
 - `std/debug.print` is an allocation-free, failure-ignoring stderr escape hatch independent of `process.Init`
 
@@ -190,12 +191,11 @@ as `math.divfloor(a, b)` resolve to ordinary functions.
 
 ## PLANNED / DEFERRED
 
-- aggregate comptime parameters and stable aggregate specialization keys
 - native Brolang variadic functions
 - exporting Brolang functions to C and broader target-specific C ABI lowering
 - non-plain C record layouts such as bitfields, packed records, flexible arrays, qualified fields, and C variadic record arguments
 - arenas, pools, build-mode heap policy, and escaping-allocation diagnostics
-- recursive type factories, reflection payloads beyond records, and type-producing unions/enums
+- recursive type factories, reflection payloads beyond records/enums, and type-producing unions/enums
 - broader Zig-style pointer/result casts beyond V1 `ptrcast!(T, ptr)`
 - sum-type ABI/layout polish, including dynamic tag-width shrinking, all-void channel collapse, and cross-module global-id determinism
 - backed/C enum composition and must-consume fallible linting