# Function rustc_expand::base::expr_to_string

source ·

    pub fn expr_to_string(
        cx: &mut ExtCtxt<'_>,
        expr: P<Expr>,
        err_msg: &'static str
    ) -> ExpandResult<Result<(Symbol, StrStyle), ErrorGuaranteed>, ()>

Expand description

Extracts a string literal from the macro expanded version of `expr`, emitting `err_msg` if `expr` is not a string literal. This does not stop compilation on error, merely emits a non-fatal error and returns `Err`.