String literals need escape sequences #185

String literals have no escape sequences, so some strings can't be written at all:

const Q: string = "say \"hi\""   // doesn't parse: a string can't contain `"`
const N: string = "a\nb"          // builds, as a backslash and an `n`, not a newline

StringLiteral is "([^"]*)", kept as written. Generators already escape what they're given ("a\nb" in a schema becomes "a\\nb" in Rust and TypeScript), so values survive; there's just no way to write a quote, a newline or a non-printing character.

Proposal: the escapes most languages share:

Any other backslash sequence is a build error, so a future escape can be added without changing what an existing string means. The same rules hold in f-strings (error messages, validator messages), alongside {{ and }}.

Compatibility: a constant or default written today with \n, \t, \0 or \\ changes value. That's acceptable before 1.0; version comparison reports each changed constant as it does any value change. Other backslashes become errors, pointing at the escape to use.

Found during the bug hunt; requested 2026-11-02.