Function inline 

fn inline(
    sema: &Semantics<'_, RootDatabase>,
    function_def_file_id: EditionedFileId,
    function: Function,
    fn_body: &BlockExpr,
    params: &[(Pat, Option<Type>, Param<'_>)],
    _: &CallInfo,
    file_editor: &SyntaxEditor,
) -> Expr