Function rustc_builtin_macros::format::parse_args

fn parse_args<'a>(
    ecx: &mut ExtCtxt<'a>,
    sp: Span,
    tts: TokenStream
) -> PResult<'a, (P<Expr>, Vec<FormatArg>, FxHashMap<Symbol, usize>)>

Parses the arguments from the given list of tokens, returning the diagnostic if there’s a parse error so we can continue parsing other format! expressions.

If parsing succeeds, the return value is:

Some((fmtstr, parsed arguments, index map for named arguments))