use std::borrow::Borrow;
use std::fmt;
use std::hash::{Hash, Hasher};
use std::mem;
use std::ptr;
use std::ops::{Deref, DerefMut};
use std::str;
use std::slice;
use array::Array;
use array::Index;
use CapacityError;
#[derive(Copy)]
pub struct ArrayString<A: Array<Item=u8>> {
xs: A,
len: A::Index,
}
impl<A: Array<Item=u8>> ArrayString<A> {
pub fn new() -> ArrayString<A> {
unsafe {
ArrayString {
xs: ::new_array(),
len: Index::from(0),
}
}
}
pub fn from(s: &str) -> Result<Self, CapacityError<&str>> {
let mut arraystr = Self::new();
try!(arraystr.push_str(s));
Ok(arraystr)
}
#[inline]
pub fn capacity(&self) -> usize { A::capacity() }
pub fn push(&mut self, c: char) -> Result<(), CapacityError<char>> {
use std::fmt::Write;
self.write_char(c).map_err(|_| CapacityError::new(c))
}
pub fn push_str<'a>(&mut self, s: &'a str) -> Result<(), CapacityError<&'a str>> {
if s.len() > self.capacity() - self.len() {
return Err(CapacityError::new(s));
}
unsafe {
let dst = self.xs.as_mut_ptr().offset(self.len() as isize);
let src = s.as_ptr();
ptr::copy_nonoverlapping(src, dst, s.len());
let newl = self.len() + s.len();
self.set_len(newl);
}
Ok(())
}
pub fn clear(&mut self) {
unsafe {
self.set_len(0);
}
}
#[inline]
pub unsafe fn set_len(&mut self, length: usize) {
debug_assert!(length <= self.capacity());
self.len = Index::from(length);
}
}
impl<A: Array<Item=u8>> Deref for ArrayString<A> {
type Target = str;
#[inline]
fn deref(&self) -> &str {
unsafe {
let sl = slice::from_raw_parts(self.xs.as_ptr(), self.len.to_usize());
str::from_utf8_unchecked(sl)
}
}
}
impl<A: Array<Item=u8>> DerefMut for ArrayString<A> {
#[inline]
fn deref_mut(&mut self) -> &mut str {
unsafe {
let sl = slice::from_raw_parts_mut(self.xs.as_mut_ptr(), self.len.to_usize());
mem::transmute(sl)
}
}
}
impl<A: Array<Item=u8>> PartialEq for ArrayString<A> {
fn eq(&self, rhs: &Self) -> bool {
**self == **rhs
}
}
impl<A: Array<Item=u8>> PartialEq<str> for ArrayString<A> {
fn eq(&self, rhs: &str) -> bool {
&**self == rhs
}
}
impl<A: Array<Item=u8>> PartialEq<ArrayString<A>> for str {
fn eq(&self, rhs: &ArrayString<A>) -> bool {
self == &**rhs
}
}
impl<A: Array<Item=u8>> Eq for ArrayString<A> { }
impl<A: Array<Item=u8>> Hash for ArrayString<A> {
fn hash<H: Hasher>(&self, h: &mut H) {
(**self).hash(h)
}
}
impl<A: Array<Item=u8>> Borrow<str> for ArrayString<A> {
fn borrow(&self) -> &str { self }
}
impl<A: Array<Item=u8>> AsRef<str> for ArrayString<A> {
fn as_ref(&self) -> &str { self }
}
impl<A: Array<Item=u8>> fmt::Debug for ArrayString<A> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { (**self).fmt(f) }
}
impl<A: Array<Item=u8>> fmt::Display for ArrayString<A> {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { (**self).fmt(f) }
}
impl<A: Array<Item=u8>> fmt::Write for ArrayString<A> {
fn write_str(&mut self, s: &str) -> fmt::Result {
self.push_str(s).map_err(|_| fmt::Error)
}
}
impl<A: Array<Item=u8> + Copy> Clone for ArrayString<A> {
fn clone(&self) -> ArrayString<A> {
*self
}
fn clone_from(&mut self, rhs: &Self) {
self.clear();
self.push_str(rhs).ok();
}
}