Surface rename of the signed integer family: s1..s64 become i1..i64
(u1..u64, usize, isize unchanged). 'string' keeps the s-prefix arm in
name classification; width parsing moves to the i-prefix arm next to
isize.
Internal TypeId tags follow the surface (.s8/.s16/.s32/.s64 ->
.i8/.i16/.i32/.i64), as do mono-key mangle fragments (ptr_i64,
tu_i64_bool) and all display/diagnostic formatting (i{d}).
Migrated in the same sweep: stdlib + examples + issue repros + FFI C
companions (shared symbol names like ffi_id_i64), expected
stdout/stderr/ir snapshots, specs.md, readme.md, CLAUDE.md/AGENTS.md,
implementation_plan.md, docs/, issue writeups. Vendored stb_image and
historical flow state left untouched.
zig build test: 426/426; examples suite: 595/595.
std.sx now contains only alias declarations (the re-export mechanism:
own decls carry one flat-import level) over three part-files: core.sx
(builtins, libc escape hatch, Source_Location/Allocator/Context/Into,
the reserved `string` decl — which needs and permits no alias), fmt.sx
(print/format/any_to_string/string ops/cstring/alloc_slice), list.sx
(List). The namespace tail is unchanged; the part-file namespaces
(core/fmt/list) carry alongside it. Consumer surface is byte-identical
— every bare prelude name resolves through the aliases (0120/0121
machinery). 37 .ir snapshots re-pinned: pure string-constant
renumbering from the changed import graph (digit-normalized diff is
empty). Gates: zig build test 426/426, suite 588/588, m3te 23/23,
game SxChess builds + bundles.
