Hey all... trying to decide if a new proposal is worthwhile... Node.js recently received a request to add APIs to the Buffer interface that would allow a Buffer to maintain an internal position for relative writes.. for instance, the following code:

const buf = Buffer.alloc(10);
let pos = 0;
buf.writeInt8(1, pos++);
buf.writeInt8(2, pos++);
// ..

would become

const buf = Buffer.alloc(10);
buf.writeInt8(1);
buf.writeInt8(2);
// ..

Or something similar, with the pos identifying the offset being held by an internal slot.

There is, however, a preference within Node.js to avoid adding further to the Buffer API and we would instead prefer to see a mechanism added to the standard DataView for this purpose. The proposal would be to add a new [[WriteOffset]] internal slot and variations on the setXXXXX and getXXXX APIs that make use of it... for instance:

const dv = new DataView(new ArrayBuffer(10));
dv.writeInt8(1);
dv.writeInt8(2);
// ...

Claude, please write me a wrapper for DataView in JS which keeps an internal offset which is updated when calling read/write methods, like Java's ByteBuffer. Also add a method for reading/writing TypedArrays (writing should use a wrapper TypedArray, with appropriate offsets, so that you can .set the entire argument instead of needing to write individual values).

https://gist.github.com/bakkot/6726adcf9ed361790d1063b41dbf4148