write

import std::fmt::write; · source

FmtWrite#

type trait FmtWrite {
    write_str(mut &this, source: Str) -> Result<(), FmtError>;
    write_char(mut &this, c: char) -> Result<(), FmtError>;
}

The sink trait every formatter writes through. It parallels io::Write but with a different error type and a stricter contract.

write_str is the one required method; write_char has a default that encodes the scalar and routes through it. Its argument is a Str, so a sink only ever sees valid UTF-8 — that invariant is what lets a text container like String be a format target. A byte sink that isn't UTF-8-constrained is an io::Write, not an FmtWrite.

Trait implementations#

implement trait FmtWrite for struct Stdout

implement trait FmtWrite for struct Stderr

implement trait FmtWrite for struct String<GlobalAlloc>