Function hints 

fn hints(
    hints: &mut Vec<InlayHint>,
    ctx: &mut InlayHintCtx,
    famous_defs: &FamousDefs<'_, '_>,
    config: &InlayHintsConfig<'_>,
    file_id: EditionedFileId,
    display_target: DisplayTarget,
    node: SyntaxNode,
)