Module std::ascii
The ASCII module defines basic string and char newtypes in Move that verify that characters are valid ASCII, and that strings consist of only valid ASCII characters.
use std::option;
use std::vector;
Struct String
The String struct holds a vector of bytes that all represent valid ASCII characters. Note that these ASCII characters may not all be printable. To determine if a String contains only "printable" characters you should use the all_characters_printable predicate defined in this module.
public struct String has copy, drop, store
Struct Char
An ASCII character.
public struct Char has copy, drop, store
Constants
An invalid ASCII character was encountered when creating an ASCII string.
const EInvalidASCIICharacter: u64 = 65536;
An invalid index was encountered when creating a substring.
const EInvalidIndex: u64 = 65537;
Function char
Convert a byte into a Char that is checked to make sure it is valid ASCII.
public fun char(byte: u8): std::ascii::Char
Function string
Convert a vector of bytes bytes into an String. Aborts if bytes contains non-ASCII characters.
public fun string(bytes: vector<u8>): std::ascii::String
Function try_string
Convert a vector of bytes bytes into an String. Returns Some(<ascii_string>) if the bytes contains all valid ASCII characters. Otherwise returns None.
public fun try_string(bytes: vector<u8>): std::option::Option<std::ascii::String>
Function all_characters_printable
Returns true if all characters in string are printable characters.
Returns false otherwise. Not all Strings are printable strings.
public fun all_characters_printable(string: &std::ascii::String): bool
Function push_char
Push a Char to the end of the string.
public fun push_char(string: &mut std::ascii::String, char: std::ascii::Char)
Function pop_char
Pop a Char from the end of the string.
public fun pop_char(string: &mut std::ascii::String): std::ascii::Char
Function length
Returns the length of the string in bytes.
public fun length(string: &std::ascii::String): u64
Function append
Append the other string to the end of string.
public fun append(string: &mut std::ascii::String, other: std::ascii::String)
Function insert
Insert the other string at the at index of string.
public fun insert(s: &mut std::ascii::String, at: u64, o: std::ascii::String)
Function substring
Copy the slice of the string from i to j into a new String.
public fun substring(string: &std::ascii::String, i: u64, j: u64): std::ascii::String
Function as_bytes
Get the inner bytes of the string as a reference
public fun as_bytes(string: &std::ascii::String): &vector<u8>
Function into_bytes
Unpack the string to get its backing bytes
public fun into_bytes(string: std::ascii::String): vector<u8>
Function byte
Unpack the char into its underlying bytes.
public fun byte(char: std::ascii::Char): u8
Function is_valid_char
Returns true if b is a valid ASCII character.
Returns false otherwise.
public fun is_valid_char(b: u8): bool
Function is_printable_char
Returns true if byte is a printable ASCII character.
Returns false otherwise.
public fun is_printable_char(byte: u8): bool
Function is_empty
Returns true if string is empty.
public fun is_empty(string: &std::ascii::String): bool
Function to_uppercase
Convert a string to its uppercase equivalent.
public fun to_uppercase(string: &std::ascii::String): std::ascii::String
Function to_lowercase
Convert a string to its lowercase equivalent.
public fun to_lowercase(string: &std::ascii::String): std::ascii::String
Function index_of
Computes the index of the first occurrence of the substr in the string.
Returns the length of the string if the substr is not found.
Returns 0 if the substr is empty.
public fun index_of(string: &std::ascii::String, substr: &std::ascii::String): u64
Function char_to_uppercase
Convert a char to its lowercase equivalent.
fun char_to_uppercase(byte: u8): u8
Function char_to_lowercase
Convert a char to its lowercase equivalent.
fun char_to_lowercase(byte: u8): u8