Std.Sync.increment

fn

This is a callable function.

What it does

Add to a counter and answer what it then holds.

The lock is what makes this safe: reading and writing a cell are two steps,

and two threads adding at once without one would each read the same number

and write the same number, losing an addition.

Read the signature

• The text after the name is the type checked by Pudu.
• Read arrows from left to right: inputs come first, and the final type is returned.
• & borrows a value for this call instead of moving or copying it.
• Names inside [ ] are type arguments, such as the item type held by a collection.
• Result makes success and recoverable failure part of the function's type.