Additional Read/Write methods for MemoryBlock

bgrommes

Could we pretty-please have ReadDouble() and WriteDouble()?

Personally, I only care about Objo's own 64-bit Double, which I assume is also IEEE standard, but someone fiddling with quantized LLM weights or certain kinds of graphics might care about 32-bit float or even "half-precision" 16-bit.

It is not far-fetched that floating point values could need to be read from / written to binary file formats as well.

The ability to read and write DateTimes would be mighty nice, too. I am not concerned about decoding DateTime components from the binary representation, just storage from and retrieval to Objo DateTImes. Probably, you can guess why ;-)

Garry

As of the next release, MemoryBlock supports reading and writing 64-bit doubles. MemoryBlock now has ReadDouble(offset) and WriteDouble(offset, value):

Var bytes As New MemoryBlock(8)
bytes.WriteDouble(0, 1.0)
Print(bytes.ToHex())  # 000000000000f03f

bytes.LittleEndian = False
bytes.WriteDouble(0, -2.5)
Print(bytes.ToHex())  # c004000000000000
Print(bytes.ReadDouble(0))  # -2.5

Reads work symmetrically, with the byte order following each block's LittleEndian setting:

# 1.0 stored in little-endian order
Var littleEndian As MemoryBlock = MemoryBlock.FromHex("000000000000f03f")
Print(littleEndian.ReadDouble(0))  # 1

# 1.0 stored in big-endian order
Var bigEndian As MemoryBlock = MemoryBlock.FromHex("3ff0000000000000")
bigEndian.LittleEndian = False
Print(bigEndian.ReadDouble(0))  # 1

A few details worth knowing:

The methods encode and decode Objo's own 64-bit IEEE 754 binary64 Double, spanning exactly eight bytes.
They respect the current LittleEndian value, which defaults to True.
Like the integer accessors, they require the complete eight-byte range to fit inside the block; invalid or out-of-bounds offsets raise an error.
Exact binary values are preserved, including negative zero, NaN, and positive and negative infinity — handy when you're exchanging data with binary file formats or packed network payloads.