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//! Traits input types have to implement to work with nom combinators
use crate::error::{ErrorKind, ParseError};
use crate::internal::{Err, IResult, Needed};
use crate::lib::std::iter::{Copied, Enumerate};
use crate::lib::std::ops::{Range, RangeFrom, RangeFull, RangeTo};
use crate::lib::std::slice::Iter;
use crate::lib::std::str::from_utf8;
use crate::lib::std::str::CharIndices;
use crate::lib::std::str::Chars;
use crate::lib::std::str::FromStr;
#[cfg(feature = "alloc")]
use crate::lib::std::string::String;
#[cfg(feature = "alloc")]
use crate::lib::std::vec::Vec;
/// Abstract method to calculate the input length
pub trait InputLength {
/// Calculates the input length, as indicated by its name,
/// and the name of the trait itself
fn input_len(&self) -> usize;
}
impl<'a, T> InputLength for &'a [T] {
#[inline]
fn input_len(&self) -> usize {
self.len()
}
}
impl<'a> InputLength for &'a str {
#[inline]
fn input_len(&self) -> usize {
self.len()
}
}
impl<'a> InputLength for (&'a [u8], usize) {
#[inline]
fn input_len(&self) -> usize {
//println!("bit input length for ({:?}, {}):", self.0, self.1);
//println!("-> {}", self.0.len() * 8 - self.1);
self.0.len() * 8 - self.1
}
}
/// Useful functions to calculate the offset between slices and show a hexdump of a slice
pub trait Offset {
/// Offset between the first byte of self and the first byte of the argument
fn offset(&self, second: &Self) -> usize;
}
impl Offset for [u8] {
fn offset(&self, second: &Self) -> usize {
let fst = self.as_ptr();
let snd = second.as_ptr();
snd as usize - fst as usize
}
}
impl<'a> Offset for &'a [u8] {
fn offset(&self, second: &Self) -> usize {
let fst = self.as_ptr();
let snd = second.as_ptr();
snd as usize - fst as usize
}
}
impl Offset for str {
fn offset(&self, second: &Self) -> usize {
let fst = self.as_ptr();
let snd = second.as_ptr();
snd as usize - fst as usize
}
}
impl<'a> Offset for &'a str {
fn offset(&self, second: &Self) -> usize {
let fst = self.as_ptr();
let snd = second.as_ptr();
snd as usize - fst as usize
}
}
/// Helper trait for types that can be viewed as a byte slice
pub trait AsBytes {
/// Casts the input type to a byte slice
fn as_bytes(&self) -> &[u8];
}
impl<'a> AsBytes for &'a str {
#[inline(always)]
fn as_bytes(&self) -> &[u8] {
(*self).as_bytes()
}
}
impl AsBytes for str {
#[inline(always)]
fn as_bytes(&self) -> &[u8] {
self.as_ref()
}
}
impl<'a> AsBytes for &'a [u8] {
#[inline(always)]
fn as_bytes(&self) -> &[u8] {
*self
}
}
impl AsBytes for [u8] {
#[inline(always)]
fn as_bytes(&self) -> &[u8] {
self
}
}
macro_rules! as_bytes_array_impls {
($($N:expr)+) => {
$(
impl<'a> AsBytes for &'a [u8; $N] {
#[inline(always)]
fn as_bytes(&self) -> &[u8] {
*self
}
}
impl AsBytes for [u8; $N] {
#[inline(always)]
fn as_bytes(&self) -> &[u8] {
self
}
}
)+
};
}
as_bytes_array_impls! {
0 1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19
20 21 22 23 24 25 26 27 28 29
30 31 32
}
/// Transforms common types to a char for basic token parsing
pub trait AsChar {
/// makes a char from self
fn as_char(self) -> char;
/// Tests that self is an alphabetic character
///
/// Warning: for `&str` it recognizes alphabetic
/// characters outside of the 52 ASCII letters
fn is_alpha(self) -> bool;
/// Tests that self is an alphabetic character
/// or a decimal digit
fn is_alphanum(self) -> bool;
/// Tests that self is a decimal digit
fn is_dec_digit(self) -> bool;
/// Tests that self is an hex digit
fn is_hex_digit(self) -> bool;
/// Tests that self is an octal digit
fn is_oct_digit(self) -> bool;
/// Gets the len in bytes for self
fn len(self) -> usize;
}
impl AsChar for u8 {
#[inline]
fn as_char(self) -> char {
self as char
}
#[inline]
fn is_alpha(self) -> bool {
(self >= 0x41 && self <= 0x5A) || (self >= 0x61 && self <= 0x7A)
}
#[inline]
fn is_alphanum(self) -> bool {
self.is_alpha() || self.is_dec_digit()
}
#[inline]
fn is_dec_digit(self) -> bool {
self >= 0x30 && self <= 0x39
}
#[inline]
fn is_hex_digit(self) -> bool {
(self >= 0x30 && self <= 0x39)
|| (self >= 0x41 && self <= 0x46)
|| (self >= 0x61 && self <= 0x66)
}
#[inline]
fn is_oct_digit(self) -> bool {
self >= 0x30 && self <= 0x37
}
#[inline]
fn len(self) -> usize {
1
}
}
impl<'a> AsChar for &'a u8 {
#[inline]
fn as_char(self) -> char {
*self as char
}
#[inline]
fn is_alpha(self) -> bool {
(*self >= 0x41 && *self <= 0x5A) || (*self >= 0x61 && *self <= 0x7A)
}
#[inline]
fn is_alphanum(self) -> bool {
self.is_alpha() || self.is_dec_digit()
}
#[inline]
fn is_dec_digit(self) -> bool {
*self >= 0x30 && *self <= 0x39
}
#[inline]
fn is_hex_digit(self) -> bool {
(*self >= 0x30 && *self <= 0x39)
|| (*self >= 0x41 && *self <= 0x46)
|| (*self >= 0x61 && *self <= 0x66)
}
#[inline]
fn is_oct_digit(self) -> bool {
*self >= 0x30 && *self <= 0x37
}
#[inline]
fn len(self) -> usize {
1
}
}
impl AsChar for char {
#[inline]
fn as_char(self) -> char {
self
}
#[inline]
fn is_alpha(self) -> bool {
self.is_ascii_alphabetic()
}
#[inline]
fn is_alphanum(self) -> bool {
self.is_alpha() || self.is_dec_digit()
}
#[inline]
fn is_dec_digit(self) -> bool {
self.is_ascii_digit()
}
#[inline]
fn is_hex_digit(self) -> bool {
self.is_ascii_hexdigit()
}
#[inline]
fn is_oct_digit(self) -> bool {
self.is_digit(8)
}
#[inline]
fn len(self) -> usize {
self.len_utf8()
}
}
impl<'a> AsChar for &'a char {
#[inline]
fn as_char(self) -> char {
*self
}
#[inline]
fn is_alpha(self) -> bool {
self.is_ascii_alphabetic()
}
#[inline]
fn is_alphanum(self) -> bool {
self.is_alpha() || self.is_dec_digit()
}
#[inline]
fn is_dec_digit(self) -> bool {
self.is_ascii_digit()
}
#[inline]
fn is_hex_digit(self) -> bool {
self.is_ascii_hexdigit()
}
#[inline]
fn is_oct_digit(self) -> bool {
self.is_digit(8)
}
#[inline]
fn len(self) -> usize {
self.len_utf8()
}
}
/// Abstracts common iteration operations on the input type
pub trait InputIter {
/// The current input type is a sequence of that `Item` type.
///
/// Example: `u8` for `&[u8]` or `char` for `&str`
type Item;
/// An iterator over the input type, producing the item and its position
/// for use with [Slice]. If we're iterating over `&str`, the position
/// corresponds to the byte index of the character
type Iter: Iterator<Item = (usize, Self::Item)>;
/// An iterator over the input type, producing the item
type IterElem: Iterator<Item = Self::Item>;
/// Returns an iterator over the elements and their byte offsets
fn iter_indices(&self) -> Self::Iter;
/// Returns an iterator over the elements
fn iter_elements(&self) -> Self::IterElem;
/// Finds the byte position of the element
fn position<P>(&self, predicate: P) -> Option<usize>
where
P: Fn(Self::Item) -> bool;
/// Get the byte offset from the element's position in the stream
fn slice_index(&self, count: usize) -> Result<usize, Needed>;
}
/// Abstracts slicing operations
pub trait InputTake: Sized {
/// Returns a slice of `count` bytes. panics if count > length
fn take(&self, count: usize) -> Self;
/// Split the stream at the `count` byte offset. panics if count > length
fn take_split(&self, count: usize) -> (Self, Self);
}
impl<'a> InputIter for &'a [u8] {
type Item = u8;
type Iter = Enumerate<Self::IterElem>;
type IterElem = Copied<Iter<'a, u8>>;
#[inline]
fn iter_indices(&self) -> Self::Iter {
self.iter_elements().enumerate()
}
#[inline]
fn iter_elements(&self) -> Self::IterElem {
self.iter().copied()
}
#[inline]
fn position<P>(&self, predicate: P) -> Option<usize>
where
P: Fn(Self::Item) -> bool,
{
self.iter().position(|b| predicate(*b))
}
#[inline]
fn slice_index(&self, count: usize) -> Result<usize, Needed> {
if self.len() >= count {
Ok(count)
} else {
Err(Needed::new(count - self.len()))
}
}
}
impl<'a> InputTake for &'a [u8] {
#[inline]
fn take(&self, count: usize) -> Self {
&self[0..count]
}
#[inline]
fn take_split(&self, count: usize) -> (Self, Self) {
let (prefix, suffix) = self.split_at(count);
(suffix, prefix)
}
}
impl<'a> InputIter for &'a str {
type Item = char;
type Iter = CharIndices<'a>;
type IterElem = Chars<'a>;
#[inline]
fn iter_indices(&self) -> Self::Iter {
self.char_indices()
}
#[inline]
fn iter_elements(&self) -> Self::IterElem {
self.chars()
}
fn position<P>(&self, predicate: P) -> Option<usize>
where
P: Fn(Self::Item) -> bool,
{
for (o, c) in self.char_indices() {
if predicate(c) {
return Some(o);
}
}
None
}
#[inline]
fn slice_index(&self, count: usize) -> Result<usize, Needed> {
let mut cnt = 0;
for (index, _) in self.char_indices() {
if cnt == count {
return Ok(index);
}
cnt += 1;
}
if cnt == count {
return Ok(self.len());
}
Err(Needed::Unknown)
}
}
impl<'a> InputTake for &'a str {
#[inline]
fn take(&self, count: usize) -> Self {
&self[..count]
}
// return byte index
#[inline]
fn take_split(&self, count: usize) -> (Self, Self) {
let (prefix, suffix) = self.split_at(count);
(suffix, prefix)
}
}
/// Dummy trait used for default implementations (currently only used for `InputTakeAtPosition` and `Compare`).
///
/// When implementing a custom input type, it is possible to use directly the
/// default implementation: If the input type implements `InputLength`, `InputIter`,
/// `InputTake` and `Clone`, you can implement `UnspecializedInput` and get
/// a default version of `InputTakeAtPosition` and `Compare`.
///
/// For performance reasons, you might want to write a custom implementation of
/// `InputTakeAtPosition` (like the one for `&[u8]`).
pub trait UnspecializedInput {}
/// Methods to take as much input as possible until the provided function returns true for the current element.
///
/// A large part of nom's basic parsers are built using this trait.
pub trait InputTakeAtPosition: Sized {
/// The current input type is a sequence of that `Item` type.
///
/// Example: `u8` for `&[u8]` or `char` for `&str`
type Item;
/// Looks for the first element of the input type for which the condition returns true,
/// and returns the input up to this position.
///
/// *streaming version*: If no element is found matching the condition, this will return `Incomplete`
fn split_at_position<P, E: ParseError<Self>>(&self, predicate: P) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool;
/// Looks for the first element of the input type for which the condition returns true
/// and returns the input up to this position.
///
/// Fails if the produced slice is empty.
///
/// *streaming version*: If no element is found matching the condition, this will return `Incomplete`
fn split_at_position1<P, E: ParseError<Self>>(
&self,
predicate: P,
e: ErrorKind,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool;
/// Looks for the first element of the input type for which the condition returns true,
/// and returns the input up to this position.
///
/// *complete version*: If no element is found matching the condition, this will return the whole input
fn split_at_position_complete<P, E: ParseError<Self>>(
&self,
predicate: P,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool;
/// Looks for the first element of the input type for which the condition returns true
/// and returns the input up to this position.
///
/// Fails if the produced slice is empty.
///
/// *complete version*: If no element is found matching the condition, this will return the whole input
fn split_at_position1_complete<P, E: ParseError<Self>>(
&self,
predicate: P,
e: ErrorKind,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool;
}
impl<T: InputLength + InputIter + InputTake + Clone + UnspecializedInput> InputTakeAtPosition
for T
{
type Item = <T as InputIter>::Item;
fn split_at_position<P, E: ParseError<Self>>(&self, predicate: P) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.position(predicate) {
Some(n) => Ok(self.take_split(n)),
None => Err(Err::Incomplete(Needed::new(1))),
}
}
fn split_at_position1<P, E: ParseError<Self>>(
&self,
predicate: P,
e: ErrorKind,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.position(predicate) {
Some(0) => Err(Err::Error(E::from_error_kind(self.clone(), e))),
Some(n) => Ok(self.take_split(n)),
None => Err(Err::Incomplete(Needed::new(1))),
}
}
fn split_at_position_complete<P, E: ParseError<Self>>(
&self,
predicate: P,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.split_at_position(predicate) {
Err(Err::Incomplete(_)) => Ok(self.take_split(self.input_len())),
res => res,
}
}
fn split_at_position1_complete<P, E: ParseError<Self>>(
&self,
predicate: P,
e: ErrorKind,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.split_at_position1(predicate, e) {
Err(Err::Incomplete(_)) => {
if self.input_len() == 0 {
Err(Err::Error(E::from_error_kind(self.clone(), e)))
} else {
Ok(self.take_split(self.input_len()))
}
}
res => res,
}
}
}
impl<'a> InputTakeAtPosition for &'a [u8] {
type Item = u8;
fn split_at_position<P, E: ParseError<Self>>(&self, predicate: P) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.iter().position(|c| predicate(*c)) {
Some(i) => Ok(self.take_split(i)),
None => Err(Err::Incomplete(Needed::new(1))),
}
}
fn split_at_position1<P, E: ParseError<Self>>(
&self,
predicate: P,
e: ErrorKind,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.iter().position(|c| predicate(*c)) {
Some(0) => Err(Err::Error(E::from_error_kind(self, e))),
Some(i) => Ok(self.take_split(i)),
None => Err(Err::Incomplete(Needed::new(1))),
}
}
fn split_at_position_complete<P, E: ParseError<Self>>(
&self,
predicate: P,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.iter().position(|c| predicate(*c)) {
Some(i) => Ok(self.take_split(i)),
None => Ok(self.take_split(self.input_len())),
}
}
fn split_at_position1_complete<P, E: ParseError<Self>>(
&self,
predicate: P,
e: ErrorKind,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.iter().position(|c| predicate(*c)) {
Some(0) => Err(Err::Error(E::from_error_kind(self, e))),
Some(i) => Ok(self.take_split(i)),
None => {
if self.is_empty() {
Err(Err::Error(E::from_error_kind(self, e)))
} else {
Ok(self.take_split(self.input_len()))
}
}
}
}
}
impl<'a> InputTakeAtPosition for &'a str {
type Item = char;
fn split_at_position<P, E: ParseError<Self>>(&self, predicate: P) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.find(predicate) {
// find() returns a byte index that is already in the slice at a char boundary
Some(i) => unsafe { Ok((self.get_unchecked(i..), self.get_unchecked(..i))) },
None => Err(Err::Incomplete(Needed::new(1))),
}
}
fn split_at_position1<P, E: ParseError<Self>>(
&self,
predicate: P,
e: ErrorKind,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.find(predicate) {
Some(0) => Err(Err::Error(E::from_error_kind(self, e))),
// find() returns a byte index that is already in the slice at a char boundary
Some(i) => unsafe { Ok((self.get_unchecked(i..), self.get_unchecked(..i))) },
None => Err(Err::Incomplete(Needed::new(1))),
}
}
fn split_at_position_complete<P, E: ParseError<Self>>(
&self,
predicate: P,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.find(predicate) {
// find() returns a byte index that is already in the slice at a char boundary
Some(i) => unsafe { Ok((self.get_unchecked(i..), self.get_unchecked(..i))) },
// the end of slice is a char boundary
None => unsafe {
Ok((
self.get_unchecked(self.len()..),
self.get_unchecked(..self.len()),
))
},
}
}
fn split_at_position1_complete<P, E: ParseError<Self>>(
&self,
predicate: P,
e: ErrorKind,
) -> IResult<Self, Self, E>
where
P: Fn(Self::Item) -> bool,
{
match self.find(predicate) {
Some(0) => Err(Err::Error(E::from_error_kind(self, e))),
// find() returns a byte index that is already in the slice at a char boundary
Some(i) => unsafe { Ok((self.get_unchecked(i..), self.get_unchecked(..i))) },
None => {
if self.is_empty() {
Err(Err::Error(E::from_error_kind(self, e)))
} else {
// the end of slice is a char boundary
unsafe {
Ok((
self.get_unchecked(self.len()..),
self.get_unchecked(..self.len()),
))
}
}
}
}
}
}
/// Indicates whether a comparison was successful, an error, or
/// if more data was needed
#[derive(Debug, PartialEq)]
pub enum CompareResult {
/// Comparison was successful
Ok,
/// We need more data to be sure
Incomplete,
/// Comparison failed
Error,
}
/// Abstracts comparison operations
pub trait Compare<T> {
/// Compares self to another value for equality
fn compare(&self, t: T) -> CompareResult;
/// Compares self to another value for equality
/// independently of the case.
///
/// Warning: for `&str`, the comparison is done
/// by lowercasing both strings and comparing
/// the result. This is a temporary solution until
/// a better one appears
fn compare_no_case(&self, t: T) -> CompareResult;
}
fn lowercase_byte(c: u8) -> u8 {
match c {
b'A'..=b'Z' => c - b'A' + b'a',
_ => c,
}
}
impl<'a, 'b> Compare<&'b [u8]> for &'a [u8] {
#[inline(always)]
fn compare(&self, t: &'b [u8]) -> CompareResult {
let pos = self.iter().zip(t.iter()).position(|(a, b)| a != b);
match pos {
Some(_) => CompareResult::Error,
None => {
if self.len() >= t.len() {
CompareResult::Ok
} else {
CompareResult::Incomplete
}
}
}
/*
let len = self.len();
let blen = t.len();
let m = if len < blen { len } else { blen };
let reduced = &self[..m];
let b = &t[..m];
if reduced != b {
CompareResult::Error
} else if m < blen {
CompareResult::Incomplete
} else {
CompareResult::Ok
}
*/
}
#[inline(always)]
fn compare_no_case(&self, t: &'b [u8]) -> CompareResult {
if self
.iter()
.zip(t)
.any(|(a, b)| lowercase_byte(*a) != lowercase_byte(*b))
{
CompareResult::Error
} else if self.len() < t.len() {
CompareResult::Incomplete
} else {
CompareResult::Ok
}
}
}
impl<
T: InputLength + InputIter<Item = u8> + InputTake + UnspecializedInput,
O: InputLength + InputIter<Item = u8> + InputTake,
> Compare<O> for T
{
#[inline(always)]
fn compare(&self, t: O) -> CompareResult {
let pos = self
.iter_elements()
.zip(t.iter_elements())
.position(|(a, b)| a != b);
match pos {
Some(_) => CompareResult::Error,
None => {
if self.input_len() >= t.input_len() {
CompareResult::Ok
} else {
CompareResult::Incomplete
}
}
}
}
#[inline(always)]
fn compare_no_case(&self, t: O) -> CompareResult {
if self
.iter_elements()
.zip(t.iter_elements())
.any(|(a, b)| lowercase_byte(a) != lowercase_byte(b))
{
CompareResult::Error
} else if self.input_len() < t.input_len() {
CompareResult::Incomplete
} else {
CompareResult::Ok
}
}
}
impl<'a, 'b> Compare<&'b str> for &'a [u8] {
#[inline(always)]
fn compare(&self, t: &'b str) -> CompareResult {
self.compare(AsBytes::as_bytes(t))
}
#[inline(always)]
fn compare_no_case(&self, t: &'b str) -> CompareResult {
self.compare_no_case(AsBytes::as_bytes(t))
}
}
impl<'a, 'b> Compare<&'b str> for &'a str {
#[inline(always)]
fn compare(&self, t: &'b str) -> CompareResult {
self.as_bytes().compare(t.as_bytes())
}
//FIXME: this version is too simple and does not use the current locale
#[inline(always)]
fn compare_no_case(&self, t: &'b str) -> CompareResult {
let pos = self
.chars()
.zip(t.chars())
.position(|(a, b)| a.to_lowercase().ne(b.to_lowercase()));
match pos {
Some(_) => CompareResult::Error,
None => {
if self.len() >= t.len() {
CompareResult::Ok
} else {
CompareResult::Incomplete
}
}
}
}
}
impl<'a, 'b> Compare<&'b [u8]> for &'a str {
#[inline(always)]
fn compare(&self, t: &'b [u8]) -> CompareResult {
AsBytes::as_bytes(self).compare(t)
}
#[inline(always)]
fn compare_no_case(&self, t: &'b [u8]) -> CompareResult {
AsBytes::as_bytes(self).compare_no_case(t)
}
}
/// Look for a token in self
pub trait FindToken<T> {
/// Returns true if self contains the token
fn find_token(&self, token: T) -> bool;
}
impl<'a> FindToken<u8> for &'a [u8] {
fn find_token(&self, token: u8) -> bool {
memchr::memchr(token, self).is_some()
}
}
impl<'a> FindToken<u8> for &'a str {
fn find_token(&self, token: u8) -> bool {
self.as_bytes().find_token(token)
}
}
impl<'a, 'b> FindToken<&'a u8> for &'b [u8] {
fn find_token(&self, token: &u8) -> bool {
self.find_token(*token)
}
}
impl<'a, 'b> FindToken<&'a u8> for &'b str {
fn find_token(&self, token: &u8) -> bool {
self.as_bytes().find_token(token)
}
}
impl<'a> FindToken<char> for &'a [u8] {
fn find_token(&self, token: char) -> bool {
self.iter().any(|i| *i == token as u8)
}
}
impl<'a> FindToken<char> for &'a str {
fn find_token(&self, token: char) -> bool {
self.chars().any(|i| i == token)
}
}
impl<'a> FindToken<char> for &'a [char] {
fn find_token(&self, token: char) -> bool {
self.iter().any(|i| *i == token)
}
}
impl<'a, 'b> FindToken<&'a char> for &'b [char] {
fn find_token(&self, token: &char) -> bool {
self.find_token(*token)
}
}
/// Look for a substring in self
pub trait FindSubstring<T> {
/// Returns the byte position of the substring if it is found
fn find_substring(&self, substr: T) -> Option<usize>;
}
impl<'a, 'b> FindSubstring<&'b [u8]> for &'a [u8] {
fn find_substring(&self, substr: &'b [u8]) -> Option<usize> {
if substr.len() > self.len() {
return None;
}
let (&substr_first, substr_rest) = match substr.split_first() {
Some(split) => split,
// an empty substring is found at position 0
// This matches the behavior of str.find("").
None => return Some(0),
};
if substr_rest.is_empty() {
return memchr::memchr(substr_first, self);
}
let mut offset = 0;
let haystack = &self[..self.len() - substr_rest.len()];
while let Some(position) = memchr::memchr(substr_first, &haystack[offset..]) {
offset += position;
let next_offset = offset + 1;
if &self[next_offset..][..substr_rest.len()] == substr_rest {
return Some(offset);
}
offset = next_offset;
}
None
}
}
impl<'a, 'b> FindSubstring<&'b str> for &'a [u8] {
fn find_substring(&self, substr: &'b str) -> Option<usize> {
self.find_substring(AsBytes::as_bytes(substr))
}
}
impl<'a, 'b> FindSubstring<&'b str> for &'a str {
//returns byte index
fn find_substring(&self, substr: &'b str) -> Option<usize> {
self.find(substr)
}
}
/// Used to integrate `str`'s `parse()` method
pub trait ParseTo<R> {
/// Succeeds if `parse()` succeeded. The byte slice implementation
/// will first convert it to a `&str`, then apply the `parse()` function
fn parse_to(&self) -> Option<R>;
}
impl<'a, R: FromStr> ParseTo<R> for &'a [u8] {
fn parse_to(&self) -> Option<R> {
from_utf8(self).ok().and_then(|s| s.parse().ok())
}
}
impl<'a, R: FromStr> ParseTo<R> for &'a str {
fn parse_to(&self) -> Option<R> {
self.parse().ok()
}
}
/// Slicing operations using ranges.
///
/// This trait is loosely based on
/// `Index`, but can actually return
/// something else than a `&[T]` or `&str`
pub trait Slice<R> {
/// Slices self according to the range argument
fn slice(&self, range: R) -> Self;
}
macro_rules! impl_fn_slice {
( $ty:ty ) => {
fn slice(&self, range: $ty) -> Self {
&self[range]
}
};
}
macro_rules! slice_range_impl {
( [ $for_type:ident ], $ty:ty ) => {
impl<'a, $for_type> Slice<$ty> for &'a [$for_type] {
impl_fn_slice!($ty);
}
};
( $for_type:ty, $ty:ty ) => {
impl<'a> Slice<$ty> for &'a $for_type {
impl_fn_slice!($ty);
}
};
}
macro_rules! slice_ranges_impl {
( [ $for_type:ident ] ) => {
slice_range_impl! {[$for_type], Range<usize>}
slice_range_impl! {[$for_type], RangeTo<usize>}
slice_range_impl! {[$for_type], RangeFrom<usize>}
slice_range_impl! {[$for_type], RangeFull}
};
( $for_type:ty ) => {
slice_range_impl! {$for_type, Range<usize>}
slice_range_impl! {$for_type, RangeTo<usize>}
slice_range_impl! {$for_type, RangeFrom<usize>}
slice_range_impl! {$for_type, RangeFull}
};
}
slice_ranges_impl! {str}
slice_ranges_impl! {[T]}
macro_rules! array_impls {
($($N:expr)+) => {
$(
impl InputLength for [u8; $N] {
#[inline]
fn input_len(&self) -> usize {
self.len()
}
}
impl<'a> InputLength for &'a [u8; $N] {
#[inline]
fn input_len(&self) -> usize {
self.len()
}
}
impl<'a> InputIter for &'a [u8; $N] {
type Item = u8;
type Iter = Enumerate<Self::IterElem>;
type IterElem = Copied<Iter<'a, u8>>;
fn iter_indices(&self) -> Self::Iter {
(&self[..]).iter_indices()
}
fn iter_elements(&self) -> Self::IterElem {
(&self[..]).iter_elements()
}
fn position<P>(&self, predicate: P) -> Option<usize>
where P: Fn(Self::Item) -> bool {
(&self[..]).position(predicate)
}
fn slice_index(&self, count: usize) -> Result<usize, Needed> {
(&self[..]).slice_index(count)
}
}
impl<'a> Compare<[u8; $N]> for &'a [u8] {
#[inline(always)]
fn compare(&self, t: [u8; $N]) -> CompareResult {
self.compare(&t[..])
}
#[inline(always)]
fn compare_no_case(&self, t: [u8;$N]) -> CompareResult {
self.compare_no_case(&t[..])
}
}
impl<'a,'b> Compare<&'b [u8; $N]> for &'a [u8] {
#[inline(always)]
fn compare(&self, t: &'b [u8; $N]) -> CompareResult {
self.compare(&t[..])
}
#[inline(always)]
fn compare_no_case(&self, t: &'b [u8;$N]) -> CompareResult {
self.compare_no_case(&t[..])
}
}
impl FindToken<u8> for [u8; $N] {
fn find_token(&self, token: u8) -> bool {
memchr::memchr(token, &self[..]).is_some()
}
}
impl<'a> FindToken<&'a u8> for [u8; $N] {
fn find_token(&self, token: &u8) -> bool {
self.find_token(*token)
}
}
)+
};
}
array_impls! {
0 1 2 3 4 5 6 7 8 9
10 11 12 13 14 15 16 17 18 19
20 21 22 23 24 25 26 27 28 29
30 31 32
}
/// Abstracts something which can extend an `Extend`.
/// Used to build modified input slices in `escaped_transform`
pub trait ExtendInto {
/// The current input type is a sequence of that `Item` type.
///
/// Example: `u8` for `&[u8]` or `char` for `&str`
type Item;
/// The type that will be produced
type Extender;
/// Create a new `Extend` of the correct type
fn new_builder(&self) -> Self::Extender;
/// Accumulate the input into an accumulator
fn extend_into(&self, acc: &mut Self::Extender);
}
#[cfg(feature = "alloc")]
impl ExtendInto for [u8] {
type Item = u8;
type Extender = Vec<u8>;
#[inline]
fn new_builder(&self) -> Vec<u8> {
Vec::new()
}
#[inline]
fn extend_into(&self, acc: &mut Vec<u8>) {
acc.extend(self.iter().cloned());
}
}
#[cfg(feature = "alloc")]
impl ExtendInto for &[u8] {
type Item = u8;
type Extender = Vec<u8>;
#[inline]
fn new_builder(&self) -> Vec<u8> {
Vec::new()
}
#[inline]
fn extend_into(&self, acc: &mut Vec<u8>) {
acc.extend_from_slice(self);
}
}
#[cfg(feature = "alloc")]
impl ExtendInto for str {
type Item = char;
type Extender = String;
#[inline]
fn new_builder(&self) -> String {
String::new()
}
#[inline]
fn extend_into(&self, acc: &mut String) {
acc.push_str(self);
}
}
#[cfg(feature = "alloc")]
impl ExtendInto for &str {
type Item = char;
type Extender = String;
#[inline]
fn new_builder(&self) -> String {
String::new()
}
#[inline]
fn extend_into(&self, acc: &mut String) {
acc.push_str(self);
}
}
#[cfg(feature = "alloc")]
impl ExtendInto for char {
type Item = char;
type Extender = String;
#[inline]
fn new_builder(&self) -> String {
String::new()
}
#[inline]
fn extend_into(&self, acc: &mut String) {
acc.push(*self);
}
}
/// Helper trait to convert numbers to usize.
///
/// By default, usize implements `From<u8>` and `From<u16>` but not
/// `From<u32>` and `From<u64>` because that would be invalid on some
/// platforms. This trait implements the conversion for platforms
/// with 32 and 64 bits pointer platforms
pub trait ToUsize {
/// converts self to usize
fn to_usize(&self) -> usize;
}
impl ToUsize for u8 {
#[inline]
fn to_usize(&self) -> usize {
*self as usize
}
}
impl ToUsize for u16 {
#[inline]
fn to_usize(&self) -> usize {
*self as usize
}
}
impl ToUsize for usize {
#[inline]
fn to_usize(&self) -> usize {
*self
}
}
#[cfg(any(target_pointer_width = "32", target_pointer_width = "64"))]
impl ToUsize for u32 {
#[inline]
fn to_usize(&self) -> usize {
*self as usize
}
}
#[cfg(target_pointer_width = "64")]
impl ToUsize for u64 {
#[inline]
fn to_usize(&self) -> usize {
*self as usize
}
}
/// Equivalent From implementation to avoid orphan rules in bits parsers
pub trait ErrorConvert<E> {
/// Transform to another error type
fn convert(self) -> E;
}
impl<I> ErrorConvert<(I, ErrorKind)> for ((I, usize), ErrorKind) {
fn convert(self) -> (I, ErrorKind) {
((self.0).0, self.1)
}
}
impl<I> ErrorConvert<((I, usize), ErrorKind)> for (I, ErrorKind) {
fn convert(self) -> ((I, usize), ErrorKind) {
((self.0, 0), self.1)
}
}
use crate::error;
impl<I> ErrorConvert<error::Error<I>> for error::Error<(I, usize)> {
fn convert(self) -> error::Error<I> {
error::Error {
input: self.input.0,
code: self.code,
}
}
}
impl<I> ErrorConvert<error::Error<(I, usize)>> for error::Error<I> {
fn convert(self) -> error::Error<(I, usize)> {
error::Error {
input: (self.input, 0),
code: self.code,
}
}
}
#[cfg(feature = "alloc")]
#[cfg_attr(feature = "docsrs", doc(cfg(feature = "alloc")))]
impl<I> ErrorConvert<error::VerboseError<I>> for error::VerboseError<(I, usize)> {
fn convert(self) -> error::VerboseError<I> {
error::VerboseError {
errors: self.errors.into_iter().map(|(i, e)| (i.0, e)).collect(),
}
}
}
#[cfg(feature = "alloc")]
#[cfg_attr(feature = "docsrs", doc(cfg(feature = "alloc")))]
impl<I> ErrorConvert<error::VerboseError<(I, usize)>> for error::VerboseError<I> {
fn convert(self) -> error::VerboseError<(I, usize)> {
error::VerboseError {
errors: self.errors.into_iter().map(|(i, e)| ((i, 0), e)).collect(),
}
}
}
impl ErrorConvert<()> for () {
fn convert(self) {}
}
#[cfg(feature = "std")]
#[cfg_attr(feature = "docsrs", doc(cfg(feature = "std")))]
/// Helper trait to show a byte slice as a hex dump
pub trait HexDisplay {
/// Converts the value of `self` to a hex dump, returning the owned
/// `String`.
fn to_hex(&self, chunk_size: usize) -> String;
/// Converts the value of `self` to a hex dump beginning at `from` address, returning the owned
/// `String`.
fn to_hex_from(&self, chunk_size: usize, from: usize) -> String;
}
#[cfg(feature = "std")]
static CHARS: &[u8] = b"0123456789abcdef";
#[cfg(feature = "std")]
impl HexDisplay for [u8] {
#[allow(unused_variables)]
fn to_hex(&self, chunk_size: usize) -> String {
self.to_hex_from(chunk_size, 0)
}
#[allow(unused_variables)]
fn to_hex_from(&self, chunk_size: usize, from: usize) -> String {
let mut v = Vec::with_capacity(self.len() * 3);
let mut i = from;
for chunk in self.chunks(chunk_size) {
let s = format!("{:08x}", i);
for &ch in s.as_bytes().iter() {
v.push(ch);
}
v.push(b'\t');
i += chunk_size;
for &byte in chunk {
v.push(CHARS[(byte >> 4) as usize]);
v.push(CHARS[(byte & 0xf) as usize]);
v.push(b' ');
}
if chunk_size > chunk.len() {
for j in 0..(chunk_size - chunk.len()) {
v.push(b' ');
v.push(b' ');
v.push(b' ');
}
}
v.push(b'\t');
for &byte in chunk {
if (byte >= 32 && byte <= 126) || byte >= 128 {
v.push(byte);
} else {
v.push(b'.');
}
}
v.push(b'\n');
}
String::from_utf8_lossy(&v[..]).into_owned()
}
}
#[cfg(feature = "std")]
impl HexDisplay for str {
#[allow(unused_variables)]
fn to_hex(&self, chunk_size: usize) -> String {
self.to_hex_from(chunk_size, 0)
}
#[allow(unused_variables)]
fn to_hex_from(&self, chunk_size: usize, from: usize) -> String {
self.as_bytes().to_hex_from(chunk_size, from)
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_offset_u8() {
let s = b"abcd123";
let a = &s[..];
let b = &a[2..];
let c = &a[..4];
let d = &a[3..5];
assert_eq!(a.offset(b), 2);
assert_eq!(a.offset(c), 0);
assert_eq!(a.offset(d), 3);
}
#[test]
fn test_offset_str() {
let s = "abcřèÂßÇd123";
let a = &s[..];
let b = &a[7..];
let c = &a[..5];
let d = &a[5..9];
assert_eq!(a.offset(b), 7);
assert_eq!(a.offset(c), 0);
assert_eq!(a.offset(d), 5);
}
}