MemoryReader

Mojo struct 🡭

MemoryReader

@memory_only
struct MemoryReader

Reader that reads from an in-memory buffer.

Use for testing, benchmarking (without disk I/O), or when FASTQ data is already in memory. Implements the same Reader trait as FileReader and GZFile.

Fields

• data (List[UInt8])
• position (Int)

Implemented traits

AnyType, ImplicitlyDestructible, Movable, Reader

Methods

__init__

fn __init__(out self, var data: List[UInt8])

Initialize with an owned List[Byte] buffer. Takes ownership of data.

Args:

• data (List[UInt8])
• self (Self)

Returns:

Self

fn __init__(out self, data: Span[UInt8])

Initialize with a Span[Byte]; bytes are copied into an internal list.

Args:

• data (Span[UInt8])
• self (Self)

Returns:

Self

fn __init__(out self, var content: String)

Initialize from a string; copies its bytes into an internal buffer.

Args:

• content (String)
• self (Self)

Returns:

Self

Raises:

fn __init__(out self, *, deinit take: Self)

Move constructor for Movable trait compliance.

Args:

• take (Self)
• self (Self)

Returns:

Self

read_to_buffer

fn read_to_buffer(mut self, mut buf: Span[UInt8, MutExternalOrigin], amt: Int, pos: Int = 0) -> UInt64

Read bytes from the memory buffer into the destination buffer.

Args:

• self (Self)
• buf (Span[UInt8, MutExternalOrigin]): The destination buffer to write into.
• amt (Int): The number of bytes to read.
• pos (Int): The position in the destination buffer to start writing.

Returns:

UInt64: The number of bytes actually read (0 if EOF).

Raises:

reset

fn reset(mut self)

Reset the read position to the start. Use to re-read the same buffer (e.g. for benchmarking).

Args:

• self (Self)