//! This module implements Nix lists. use std::ops::Index; use std::rc::Rc; use serde::Deserialize; use super::thunk::ThunkSet; use super::TotalDisplay; use super::Value; #[repr(transparent)] #[derive(Clone, Debug, Deserialize)] pub struct NixList(Rc>); impl TotalDisplay for NixList { fn total_fmt(&self, f: &mut std::fmt::Formatter<'_>, set: &mut ThunkSet) -> std::fmt::Result { f.write_str("[ ")?; for v in self { v.total_fmt(f, set)?; f.write_str(" ")?; } f.write_str("]") } } impl From> for NixList { fn from(vs: Vec) -> Self { Self(Rc::new(vs)) } } impl NixList { pub fn len(&self) -> usize { self.0.len() } pub fn get(&self, i: usize) -> Option<&Value> { self.0.get(i) } pub fn is_empty(&self) -> bool { self.0.is_empty() } pub fn construct(count: usize, stack_slice: Vec) -> Self { debug_assert!( count == stack_slice.len(), "NixList::construct called with count == {}, but slice.len() == {}", count, stack_slice.len(), ); NixList(Rc::new(stack_slice)) } pub fn iter(&self) -> std::slice::Iter { self.0.iter() } pub fn ptr_eq(&self, other: &Self) -> bool { Rc::ptr_eq(&self.0, &other.0) } pub fn into_inner(self) -> Vec { Rc::try_unwrap(self.0).unwrap_or_else(|rc| (*rc).clone()) } } impl IntoIterator for NixList { type Item = Value; type IntoIter = std::vec::IntoIter; fn into_iter(self) -> Self::IntoIter { self.into_inner().into_iter() } } impl<'a> IntoIterator for &'a NixList { type Item = &'a Value; type IntoIter = std::slice::Iter<'a, Value>; fn into_iter(self) -> Self::IntoIter { self.0.iter() } } impl Index for NixList { type Output = Value; fn index(&self, index: usize) -> &Self::Output { &self.0[index] } }