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use core::ops::RangeBounds;
use crate::{
char_slice, char_slice_mut, char_split_at, char_split_at_mut, copy_to,
errors::{LenNotEqual, ReplaceWithPadCharError, ReplaceWithPadError, ReplacementTooLong},
iter::{CharMutRefs, CharRefs},
replace, replace_with_pad, replace_with_pad_char, replace_with_pad_left,
replace_with_pad_left_char, replace_with_pad_left_space, replace_with_pad_space, Char,
};
/// The `StrExt` trait adds some methods to string types, many of which operate on character indexes and with character references.
///
/// To use its methods, import it with a use statement.
/// ```
/// use mut_str::StrExt;
/// ```
pub trait StrExt {
/// The output string type for string operations.
type Output: ?Sized;
/// The iterator type for iterating over [`Char`] references.
type Iter<'a>: Iterator<Item = &'a Char>
where
Self: 'a;
/// The iterator type for iterating over mutable [`Char`] references.
type IterMut<'a>: Iterator<Item = &'a mut Char>
where
Self: 'a;
#[must_use]
/// Get a character reference from the string and an index.
///
/// ```
/// use mut_str::StrExt;
///
/// let s = "Hello, World!";
/// let c = s.get_char(1).unwrap();
///
/// assert_eq!(c, 'e');
/// ```
fn get_char(&self, i: usize) -> Option<&Char>;
#[must_use]
/// Get a mutable character reference from the mutable string and an index.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("Hello, World!");
/// let c = owned_s.get_char_mut(1).unwrap();
///
/// assert_eq!(c, 'e');
/// ```
fn get_char_mut(&mut self, i: usize) -> Option<&mut Char>;
#[must_use]
/// Slice the string in units of UTF-8 characters.
/// If `range` is out of bounds, `None` will be returned.
///
/// ```
/// use mut_str::StrExt;
///
/// let s = "Hello, World!";
///
/// let hello = s.char_slice(..5).unwrap();
/// assert_eq!(hello, "Hello");
///
/// let world = s.char_slice(7..12).unwrap();
/// assert_eq!(world, "World");
/// ```
fn char_slice<R: RangeBounds<usize>>(&self, range: R) -> Option<&Self::Output>;
#[must_use]
/// Slice the mutable string in units of UTF-8 characters.
/// If `range` is out of bounds, `None` will be returned.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("Hello, World!");
///
/// let hello = owned_s.char_slice_mut(..5).unwrap();
/// assert_eq!(hello, "Hello");
///
/// let world = owned_s.char_slice_mut(7..12).unwrap();
/// assert_eq!(world, "World");
/// ```
fn char_slice_mut<R: RangeBounds<usize>>(&mut self, range: R) -> Option<&mut Self::Output>;
#[must_use]
/// Divide the string into two at an index in units of UTF-8 characters.
/// If `mid` is out of bounds, `None` will be returned.
///
/// ```
/// use mut_str::StrExt;
///
/// let s = "Hello, World!";
///
/// let (l, r) = s.char_split_at(6).unwrap();
/// assert_eq!(l, "Hello,");
/// assert_eq!(r, " World!");
/// ```
fn char_split_at(&self, mid: usize) -> Option<(&Self::Output, &Self::Output)>;
#[must_use]
/// Divide the mutable string into two at an index in units of UTF-8 characters.
/// If `mid` is out of bounds, `None` will be returned.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("Hello, World!");
///
/// let (l, r) = owned_s.char_split_at_mut(6).unwrap();
/// assert_eq!(l, "Hello,");
/// assert_eq!(r, " World!");
/// ```
fn char_split_at_mut(&mut self, mid: usize) -> Option<(&mut Self::Output, &mut Self::Output)>;
#[must_use]
/// Get an iterator over character references in the string.
///
/// ```
/// use mut_str::StrExt;
///
/// let s = "Hello, World!";
///
/// s.ref_iter()
/// .zip(s.chars())
/// .for_each(|(x, y)| assert_eq!(x, y));
/// ```
fn ref_iter(&self) -> Self::Iter<'_>;
#[must_use]
/// Get an iterator over mutable character references in the string.
///
/// ```
/// use mut_str::StrExt;
///
/// let s = "Hello, World!";
/// let mut owned_s = Box::<str>::from(s);
///
/// owned_s.mut_iter()
/// .zip(s.chars())
/// .for_each(|(x, y)| assert_eq!(x, y));
/// ```
fn mut_iter(&mut self) -> Self::IterMut<'_>;
/// Copy the string to a byte buffer and get the new string containing the inserted character.
/// Returns `None` if `buffer` is shorter than the string.
///
/// ```
/// use mut_str::StrExt;
///
/// let s = "Hello, World!";
/// let mut buffer = [0; 50];
/// let new_s = s.copy_to(&mut buffer).unwrap();
///
/// assert_eq!(new_s, s);
/// ```
fn copy_to<'a>(&self, buffer: &'a mut [u8]) -> Option<&'a mut Self::Output>;
/// Replace the mutable string with another of the same length.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("World!");
///
/// owned_s.replace_with("🌍!!").unwrap();
/// assert_eq!(&*owned_s, "🌍!!");
///
/// owned_s.replace_with("aaaaaa").unwrap();
/// assert_eq!(&*owned_s, "aaaaaa");
/// ```
///
/// # Errors
/// - If `s` and `r`, when utf8 encoded, do not have the same length, [`LenNotEqual`] will be returned.
fn replace_with<'a>(&'a mut self, r: &str) -> Result<&'a mut str, LenNotEqual>;
/// Replace the mutable string with another of the same length or shorter.
/// The remaining bytes will be filled with spaces.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("World!");
///
/// owned_s.replace_with_pad_space("🌍").unwrap();
/// assert_eq!(&*owned_s, "🌍 ");
///
/// owned_s.replace_with_pad_space("aaaa").unwrap();
/// assert_eq!(&*owned_s, "aaaa ");
/// ```
///
/// # Errors
/// - If `r`, when utf8 encoded, is longer than `s`, when utf8 encoded, [`ReplacementTooLong`] will be returned.
fn replace_with_pad_space<'a>(&'a mut self, r: &str)
-> Result<&'a mut str, ReplacementTooLong>;
/// Replace the mutable string with another of the same length or shorter.
/// The remaining bytes will be filled with `pad`.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("World!");
///
/// owned_s.replace_with_pad("🌍", b'!').unwrap();
/// assert_eq!(&*owned_s, "🌍!!");
///
/// owned_s.replace_with_pad("aaaa", b'b').unwrap();
/// assert_eq!(&*owned_s, "aaaabb");
/// ```
///
/// # Errors
/// - If `pad` is not valid utf8, [`ReplaceWithPadError::InvalidPad`] will be returned.
/// - If `r`, when utf8 encoded, is longer than `s`, when utf8 encoded, [`ReplaceWithPadError::ReplacementLen`] will be returned.
fn replace_with_pad<'a>(
&'a mut self,
r: &str,
pad: u8,
) -> Result<&'a mut str, ReplaceWithPadError>;
/// Replace the mutable string with another of the same length or shorter.
/// The remaining bytes will be filled with `pad`, which must be one byte long.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("World!");
///
/// owned_s.replace_with_pad_char("🌍", '!').unwrap();
/// assert_eq!(&*owned_s, "🌍!!");
///
/// owned_s.replace_with_pad_char("aaaa", 'b').unwrap();
/// assert_eq!(&*owned_s, "aaaabb");
/// ```
///
/// # Errors
/// - If `pad_char`, when utf8 encoded, is longer than `Self`, [`ReplaceWithPadCharError::PadCharTooLong`] will be returned.
/// - If `r`, when utf8 encoded, is longer than `s`, when utf8 encoded, [`ReplaceWithPadCharError::ReplacementLen`] will be returned.
fn replace_with_pad_char<'a, C>(
&'a mut self,
r: &str,
pad_char: C,
) -> Result<&'a mut str, ReplaceWithPadCharError>
where
C: Into<char>;
/// Replace the mutable string with another of the same length or shorter, right aligned.
/// The remaining bytes before the string will be filled with spaces.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("World!");
///
/// owned_s.replace_with_pad_left_space("🌍").unwrap();
/// assert_eq!(&*owned_s, " 🌍");
///
/// owned_s.replace_with_pad_left_space("aaaa").unwrap();
/// assert_eq!(&*owned_s, " aaaa");
/// ```
///
/// # Errors
/// - If `r`, when utf8 encoded, is longer than `s`, when utf8 encoded, [`ReplacementTooLong`] will be returned.
fn replace_with_pad_left_space<'a>(
&'a mut self,
r: &str,
) -> Result<&'a mut Self::Output, ReplacementTooLong>;
/// Replace the mutable string with another of the same length or shorter, right aligned.
/// The remaining bytes before the string will be filled with `pad`.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("World!");
///
/// owned_s.replace_with_pad_left("🌍", b'!').unwrap();
/// assert_eq!(&*owned_s, "!!🌍");
///
/// owned_s.replace_with_pad_left("aaaa", b'b').unwrap();
/// assert_eq!(&*owned_s, "bbaaaa");
/// ```
///
/// # Errors
/// - If `pad` is not valid utf8, [`ReplaceWithPadError::InvalidPad`] will be returned.
/// - If `r`, when utf8 encoded, is longer than `s`, when utf8 encoded, [`ReplaceWithPadError::ReplacementLen`] will be returned.
fn replace_with_pad_left<'a>(
&'a mut self,
r: &str,
pad: u8,
) -> Result<&'a mut Self::Output, ReplaceWithPadError>;
/// Replace the mutable string with another of the same length or shorter, right aligned.
/// The remaining bytes before the string will be filled with `char`, which must be one byte long.
///
/// ```
/// use mut_str::StrExt;
///
/// let mut owned_s = Box::<str>::from("World!");
///
/// owned_s.replace_with_pad_left_char("🌍", '!').unwrap();
/// assert_eq!(&*owned_s, "!!🌍");
///
/// owned_s.replace_with_pad_left_char("aaaa", 'b').unwrap();
/// assert_eq!(&*owned_s, "bbaaaa");
/// ```
///
/// # Errors
/// - If `pad_char`, when utf8 encoded, is longer than `Self`, [`ReplaceWithPadCharError::PadCharTooLong`] will be returned.
/// - If `r`, when utf8 encoded, is longer than `s`, when utf8 encoded, [`ReplaceWithPadCharError::ReplacementLen`] will be returned.
fn replace_with_pad_left_char<'a, C>(
&'a mut self,
r: &str,
pad_char: C,
) -> Result<&'a mut Self::Output, ReplaceWithPadCharError>
where
C: Into<char>;
}
impl StrExt for str {
type Output = Self;
type Iter<'a> = CharRefs<'a>;
type IterMut<'a> = CharMutRefs<'a>;
#[inline]
fn get_char(&self, i: usize) -> Option<&Char> {
Char::get(self, i)
}
#[inline]
fn get_char_mut(&mut self, i: usize) -> Option<&mut Char> {
Char::get_mut(self, i)
}
#[inline]
fn char_slice<R: RangeBounds<usize>>(&self, range: R) -> Option<&Self::Output> {
char_slice(self, range)
}
#[inline]
fn char_slice_mut<R: RangeBounds<usize>>(&mut self, range: R) -> Option<&mut Self::Output> {
char_slice_mut(self, range)
}
#[inline]
fn char_split_at(&self, mid: usize) -> Option<(&Self::Output, &Self::Output)> {
char_split_at(self, mid)
}
#[inline]
fn char_split_at_mut(&mut self, mid: usize) -> Option<(&mut Self::Output, &mut Self::Output)> {
char_split_at_mut(self, mid)
}
#[inline]
fn ref_iter(&self) -> Self::Iter<'_> {
CharRefs::from(self)
}
#[inline]
fn mut_iter(&mut self) -> Self::IterMut<'_> {
CharMutRefs::from(self)
}
#[inline]
fn copy_to<'a>(&self, buffer: &'a mut [u8]) -> Option<&'a mut Self::Output> {
copy_to(self, buffer)
}
#[inline]
fn replace_with<'a>(&'a mut self, r: &str) -> Result<&'a mut str, LenNotEqual> {
replace(self, r)
}
#[inline]
fn replace_with_pad_space<'a>(
&'a mut self,
r: &str,
) -> Result<&'a mut str, ReplacementTooLong> {
replace_with_pad_space(self, r)
}
#[inline]
fn replace_with_pad<'a>(
&'a mut self,
r: &str,
pad: u8,
) -> Result<&'a mut str, ReplaceWithPadError> {
replace_with_pad(self, r, pad)
}
#[inline]
fn replace_with_pad_char<'a, C>(
&'a mut self,
r: &str,
pad_char: C,
) -> Result<&'a mut str, ReplaceWithPadCharError>
where
C: Into<char>,
{
replace_with_pad_char(self, r, pad_char)
}
#[inline]
fn replace_with_pad_left_space(
&mut self,
r: &str,
) -> Result<&mut Self::Output, ReplacementTooLong> {
replace_with_pad_left_space(self, r)
}
#[inline]
fn replace_with_pad_left(
&mut self,
r: &str,
pad: u8,
) -> Result<&mut Self::Output, ReplaceWithPadError> {
replace_with_pad_left(self, r, pad)
}
#[inline]
fn replace_with_pad_left_char<C>(
&mut self,
r: &str,
pad_char: C,
) -> Result<&mut Self::Output, ReplaceWithPadCharError>
where
C: Into<char>,
{
replace_with_pad_left_char(self, r, pad_char)
}
}