Is there an inbuilt constant for Anchor discriminator size?

Question

I know I can use InitSpace to automatically calculate space for an account.

I know InitSpace doesn't include the Anchor discriminator, so I still to add another 8 bytes for the discriminator. I can add a constant for ANCHOR_DISCRIMINATOR_SIZE:

#[constant]
pub const ANCHOR_DISCRIMINATOR_SIZE: usize = 8;

But requiring every Anchor developer to create this constant, or use magic numbers, seems very odd. Is there an inbuilt constant for Anchor discriminator size?

Answer 1

I’ve looked through anchor’s repo.

There’s no any constant value written in the rust code to declare discriminator is 8 bytes long.

But in anchor’s TypeScript client there’s a constant value for DISCRIMINATOR_SIZE.

Maybe try opening up an issue in anchor’s repo they can help you more on this.