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Mojo struct

Error

This type represents an Error.

Fields​

  • ​data (UnsafePointer[SIMD[uint8, 1]]): A pointer to the beginning of the string data being referenced.
  • ​loaded_length (Int): The length of the string being referenced. Error instances conditionally own their error message. To reduce the size of the error instance we use the sign bit of the length field to store the ownership value. When loaded_length is negative it indicates ownership and a free is executed in the destructor.

Implemented traits​

AnyType, Boolable, CollectionElement, CollectionElementNew, Copyable, ExplicitlyCopyable, Movable, Representable, Stringable, Writable, _CurlyEntryFormattable

Methods​

__init__​

__init__(out self)

Default constructor.

__init__(out self, value: StringLiteral)

Construct an Error object with a given string literal.

Args:

  • ​value (StringLiteral): The error message.

__init__(out self, src: String)

Construct an Error object with a given string.

Args:

  • ​src (String): The error message.

__init__(out self, src: StringRef)

Construct an Error object with a given string ref.

Args:

  • ​src (StringRef): The error message.

__init__(out self, *, other: Self)

Copy the object.

Args:

  • ​other (Self): The value to copy.

__copyinit__​

__copyinit__(out self, existing: Self)

Creates a deep copy of an existing error.

Args:

  • ​existing (Self): The error to copy from.

__del__​

__del__(owned self)

Releases memory if allocated.

__bool__​

__bool__(self) -> Bool

Returns True if the error is set and false otherwise.

Returns:

True if the error object contains a value and False otherwise.

__str__​

__str__(self) -> String

Converts the Error to string representation.

Returns:

A String of the error message.

write_to​

write_to[W: Writer](self, inout writer: W)

Formats this error to the provided Writer.

Parameters:

  • ​W (Writer): A type conforming to the Writable trait.

Args:

  • ​writer (W): The object to write to.

__repr__​

__repr__(self) -> String

Converts the Error to printable representation.

Returns:

A printable representation of the error message.

unsafe_cstr_ptr​

unsafe_cstr_ptr(self) -> UnsafePointer[SIMD[int8, 1]]

Retrieves a C-string-compatible pointer to the underlying memory.

The returned pointer is guaranteed to be NUL terminated, and not null.

Returns:

The pointer to the underlying memory.