Function fmt_function

datafusion/expr/src/expr.rs:3725–3742

(
    f: &mut Formatter,
    fun: &str,
    distinct: bool,
    args: &[Expr],
    display: bool,
)

}

fn fmt_function(
    f: &mut Formatter,
    fun: &str,
    distinct: bool,
    args: &[Expr],
    display: bool,
) -> fmt::Result {
    let args: Vec<String> = match display {
        true => args.iter().map(|arg| format!("{arg}")).collect(),
        false => args.iter().map(|arg| format!("{arg:?}")).collect(),
    };

    let distinct_str = match distinct {
        true => "DISTINCT ",
        false => "",
    };
    write!(f, "{}({}{})", fun, distinct_str, args.join(", "))
}

/// The name of the column (field) that this `Expr` will produce in the physical plan.
/// The difference from [Expr::schema_name] is that top-level columns are unqualified.