std::ascii::AsciiExt - Rust
Description: API documentation for the Rust `AsciiExt` trait in crate `std`.
Keywords: rust, rustlang, rust-lang, AsciiExt

# Trait std::ascii::AsciiExt 1.0.0 [−] [src]

    pub trait AsciiExt {
        type Owned;
        fn is_ascii(&self) -> bool;
        fn to_ascii_uppercase(&self) -> Self::Owned;
        fn to_ascii_lowercase(&self) -> Self::Owned;
        fn eq_ignore_ascii_case(&self, other: &Self) -> bool;
        fn make_ascii_uppercase(&mut self);
        fn make_ascii_lowercase(&mut self);

        fn is_ascii_alphabetic(&self) -> bool { ... }
        fn is_ascii_uppercase(&self) -> bool { ... }
        fn is_ascii_lowercase(&self) -> bool { ... }
        fn is_ascii_alphanumeric(&self) -> bool { ... }
        fn is_ascii_digit(&self) -> bool { ... }
        fn is_ascii_hexdigit(&self) -> bool { ... }
        fn is_ascii_punctuation(&self) -> bool { ... }
        fn is_ascii_graphic(&self) -> bool { ... }
        fn is_ascii_whitespace(&self) -> bool { ... }
        fn is_ascii_control(&self) -> bool { ... }
    }

Extension methods for ASCII-subset only operations.

Be aware that operations on seemingly non-ASCII characters can sometimes have unexpected results. Consider this example:

    use std::ascii::AsciiExt;

    assert_eq!(AsciiExt::to_ascii_uppercase("café"), "CAFÉ");
    assert_eq!(AsciiExt::to_ascii_uppercase("café"), "CAFé");Run

In the first example, the lowercased string is represented `"cafe\u{301}"` (the last character is an acute accent combining character). Unlike the other characters in the string, the combining character will not get mapped to an uppercase variant, resulting in `"CAFE\u{301}"`. In the second example, the lowercased string is represented `"caf\u{e9}"` (the last character is a single Unicode character representing an 'e' with an acute accent). Since the last character is defined outside the scope of ASCII, it will not get mapped to an uppercase variant, resulting in `"CAF\u{e9}"`.

## Associated Types

### `type Owned`

Container type for copied ASCII characters.

## Required Methods

### `fn is_ascii(&self) -> bool`

Checks if the value is within the ASCII range.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn to_ascii_uppercase(&self) -> Self::Owned`

Makes a copy of the value in its ASCII upper case equivalent.

ASCII letters 'a' to 'z' are mapped to 'A' to 'Z', but non-ASCII letters are unchanged.

To uppercase the value in-place, use `make_ascii_uppercase`.

To uppercase ASCII characters in addition to non-ASCII characters, use `str::to_uppercase`.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn to_ascii_lowercase(&self) -> Self::Owned`

Makes a copy of the value in its ASCII lower case equivalent.

ASCII letters 'A' to 'Z' are mapped to 'a' to 'z', but non-ASCII letters are unchanged.

To lowercase the value in-place, use `make_ascii_lowercase`.

To lowercase ASCII characters in addition to non-ASCII characters, use `str::to_lowercase`.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn eq_ignore_ascii_case(&self, other: &Self) -> bool`

Checks that two values are an ASCII case-insensitive match.

Same as `to_ascii_lowercase(a) == to_ascii_lowercase(b)`, but without allocating and copying temporaries.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn make_ascii_uppercase(&mut self)`
1.9.0

Converts this type to its ASCII upper case equivalent in-place.

ASCII letters 'a' to 'z' are mapped to 'A' to 'Z', but non-ASCII letters are unchanged.

To return a new uppercased value without modifying the existing one, use `to_ascii_uppercase`.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn make_ascii_lowercase(&mut self)`
1.9.0

Converts this type to its ASCII lower case equivalent in-place.

ASCII letters 'A' to 'Z' are mapped to 'a' to 'z', but non-ASCII letters are unchanged.

To return a new lowercased value without modifying the existing one, use `to_ascii_lowercase`.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

## Provided Methods

### `fn is_ascii_alphabetic(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII alphabetic character: U+0041 'A' ... U+005A 'Z' or U+0061 'a' ... U+007A 'z'. For strings, true if all characters in the string are ASCII alphabetic.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_uppercase(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII uppercase character: U+0041 'A' ... U+005A 'Z'. For strings, true if all characters in the string are ASCII uppercase.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_lowercase(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII lowercase character: U+0061 'a' ... U+007A 'z'. For strings, true if all characters in the string are ASCII lowercase.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_alphanumeric(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII alphanumeric character: U+0041 'A' ... U+005A 'Z', U+0061 'a' ... U+007A 'z', or U+0030 '0' ... U+0039 '9'. For strings, true if all characters in the string are ASCII alphanumeric.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_digit(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII decimal digit: U+0030 '0' ... U+0039 '9'. For strings, true if all characters in the string are ASCII digits.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_hexdigit(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII hexadecimal digit: U+0030 '0' ... U+0039 '9', U+0041 'A' ... U+0046 'F', or U+0061 'a' ... U+0066 'f'. For strings, true if all characters in the string are ASCII hex digits.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_punctuation(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII punctuation character:

U+0021 ... U+002F `! " # $ % & ' ( ) * + , - . /` U+003A ... U+0040 `: ; < = > ? @` U+005B ... U+0060 `[ \\ ] ^ _ `` U+007B ... U+007E `{ | } ~`

For strings, true if all characters in the string are ASCII punctuation.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_graphic(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII graphic character: U+0021 '@' ... U+007E '~'. For strings, true if all characters in the string are ASCII graphic characters.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_whitespace(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII whitespace character: U+0020 SPACE, U+0009 HORIZONTAL TAB, U+000A LINE FEED, U+000C FORM FEED, or U+000D CARRIAGE RETURN. For strings, true if all characters in the string are ASCII whitespace.

Rust uses the WhatWG Infra Standard's definition of ASCII whitespace. There are several other definitions in wide use. For instance, the POSIX locale includes U+000B VERTICAL TAB as well as all the above characters, but—from the very same specification—the default rule for "field splitting" in the Bourne shell considers only SPACE, HORIZONTAL TAB, and LINE FEED as whitespace.

If you are writing a program that will process an existing file format, check what that format's definition of whitespace is before using this function.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

### `fn is_ascii_control(&self) -> bool`

🔬 This is a nightly-only experimental API. (`ascii_ctype` #39658)

Checks if the value is an ASCII control character: U+0000 NUL ... U+001F UNIT SEPARATOR, or U+007F DELETE. Note that most ASCII whitespace characters are control characters, but SPACE is not.

# Note

This method will be deprecated in favor of the identically-named inherent methods on `u8`, `char`, `[u8]` and `str`.

## Implementors

- [src]
  `impl AsciiExt for u8 type Owned = u8;`
- [src]
  `impl AsciiExt for char type Owned = char;`
- [src]
  `impl AsciiExt for [u8] type Owned = Vec<u8>;`
- [src]
  `impl AsciiExt for str type Owned = String;`

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