string

Module

Implements basic object methods for working with strings.

These are Mojo built-ins, so you don’t need to import them.

String

Represents a mutable string.

Functions:

__init__

__init__(inout self: Self)

Construct an empty string.

__init__(inout self: Self, str: StringRef)

Construct a string from a StringRef object.

Args:

• str (StringRef): The StringRef from which to construct this string object.

__init__(inout self: Self, str: StringLiteral)

Constructs a String value given a constant string.

Args:

• str (StringLiteral): The input constant string.

__init__(inout self: Self, val: Bool)

Constructs a string representing an bool value.

Args:

• val (Bool): The boolean value.

__init__(inout self: Self, num: Int)

Constructs a string representing an integer value.

Args:

• num (Int): The integer value.

__init__(inout self: Self, num: FloatLiteral)

Constructs a string representing a float value.

Args:

• num (FloatLiteral): The float value.

__init__[type: DType, simd_width: Int](inout self: Self, vec: SIMD[type, simd_width])

Constructs a string for a given SIMD value.

Parameters:

• type (DType): The dtype of the SIMD value.
• simd_width (Int): The width of the SIMD value.

Args:

• vec (SIMD[type, simd_width]): The SIMD value.

__init__[type: DType, simd_width: Int](inout self: Self, vec: ComplexSIMD[type, simd_width])

Constructs a string for a given complex value.

Parameters:

• type (DType): The dtype of the SIMD value.
• simd_width (Int): The width of the SIMD value.

Args:

• vec (ComplexSIMD[type, simd_width]): The complex value.

__init__[size: Int](inout self: Self, tuple: StaticIntTuple[size])

Constructs a string from a given StaticIntTuple.

Parameters:

• size (Int): The size of the tuple.

Args:

• tuple (StaticIntTuple[size]): The input tuple.

__init__(inout self: Self, ptr: Pointer[SIMD[si8, 1]], len: Int)

Creates a string from the buffer. Note that the string now owns the buffer.

Args:

• ptr (Pointer[SIMD[si8, 1]]): The pointer to the buffer.
• len (Int): The length of the buffer.

__copyinit__

__copyinit__(inout self: Self, existing: Self)

Creates a deep copy of an existing string.

Args:

• existing (Self): The string to copy.

__del__

__del__(owned self: Self)

Deallocates the string.

__bool__

__bool__(self: Self) -> Bool

Checks if the string is empty.

Returns:

True if the string is empty and False otherwise.

__getitem__

__getitem__(self: Self, idx: Int) -> Self

Gets the character at the specified position.

Args:

• idx (Int): The index value.

Returns:

A new string containing the character at the specified position.

__getitem__(self: Self, span: slice) -> Self

Gets the sequence of characters at the specified positions.

Args:

• span (slice): A slice that specifies positions of the new substring.

Returns:

A new string containing the string at the specified positions.

__eq__

__eq__(self: Self, other: Self) -> Bool

Compares two Strings if they have the same values.

Args:

• other (Self): The rhs of the operation.

Returns:

True if the Strings are equal and False otherwise.

__ne__

__ne__(self: Self, other: Self) -> Bool

Compares two Strings if they do not have the same values.

Args:

• other (Self): The rhs of the operation.

Returns:

True if the Strings are not equal and False otherwise.

__add__

__add__(self: Self, other: Self) -> Self

Creates a string by appending another string at the end.

Args:

• other (Self): The string to append.

Returns:

The new constructed string.

__radd__

__radd__(self: Self, other: Self) -> Self

Creates a string by prepending another string to the start.

Args:

• other (Self): The string to prepend.

Returns:

The new constructed string.

__radd__(self: Self, other: StringLiteral) -> Self

Creates a string by prepending another string to the start.

Args:

• other (StringLiteral): The string to prepend.

Returns:

The new constructed string.

__iadd__

__iadd__(inout self: Self, other: Self)

Appends another string to this string.

Args:

• other (Self): The string to append.

__len__

__len__(self: Self) -> Int

Returns the string length.

Returns:

The string length.

join

join[rank: Int](self: Self, elems: StaticIntTuple[rank]) -> Self

Joins the elements from the tuple using the current string as a delimiter.

Parameters:

• rank (Int): The size of the tuple.

Args:

• elems (StaticIntTuple[rank]): The input tuple.

Returns:

The joined string.

join(self: Self, *lst: Int) -> Self

Joins integer elements using the current string as a delimiter.

Args:

• lst (*Int): The input values.

Returns:

The joined string.

join(self: Self, *strs: Self) -> Self

Joins string elements using the current string as a delimiter.

Args:

• strs (*Self): The input values.

Returns:

The joined string.

ord

ord(s: String) -> Int

Returns an integer that represents the given one-character string.

Given a string representing one ASCII character, return an integer representing the code point of that character. For example, ord("a") returns the integer 97. This is the inverse of the chr() function.

Args:

• s (String): The input string, which must contain only a single character.

Returns:

An integer representing the code point of the given character.

chr

chr(c: Int) -> String

Returns a string based on the given Unicode code point.

Returns the string representing a character whose code point (which must be a positive integer between 0 and 255) is the integer i. For example, chr(97) returns the string "a". This is the inverse of the ord() function.

Args:

• c (Int): An integer between 0 and 255 that represents a code point.

Returns:

A string containing a single character based on the given code point.

atol

atol(str: String) -> Int

Parses the given string as a base-10 integer and returns that value.

For example, atol("19") returns 19. If the given string cannot be parsed as an integer value, an error is raised. For example, atol("hi") raises an error.

Args:

• str (String): A string to be parsed as a base-10 integer.

Returns:

An integer value that represents the string, or otherwise raises.

isdigit

isdigit(c: SIMD[si8, 1]) -> Bool

Determines whether the given character is a digit [0-9].

Args:

• c (SIMD[si8, 1]): The character to check.

Returns:

True if the character is a digit.