Answering your readability point directly: the compiler's own string-building —
left uglier by the 7c `+` migration, e.g. `emit_bind(("load i32, ptr " + ip))` —
now reads as interpolation:
emit_bind(("load i32, ptr " + ip)) -> emit_bind(`load i32, ptr {ip}`)
emit_bind(("icmp eq i32 " + (kv + (", " + itoa(ak)))))
-> emit_bind(`icmp eq i32 {kv}, {itoa(ak)}`)
perr(("assign to unknown " + t.s)) -> perr(`assign to unknown {t.s}`)
164 concat chains across selfhost converted by a tool that flattens the `+` tree,
keeps call/index parens (only grouping parens are rewritten), and converts only
**brace-free** literals — LLVM IR structure strings full of `{`/`}` stay as `+`
rather than becoming awkward `{{`/`}}`. No new language surface; interpolation
already desugars to the same concat.
Reseeded (22565 lines); C-free fixpoint holds byte-for-byte (the strongest proof
the reconstruction is exact); goldens identical; 18/18.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>