Peek operation for stacks

[yoavweiss]

What problem are you trying to solve?

I have a spec draft in which I want to know what's the last member of a stack.

What solutions exist today?

Right now there are two ways to do that:

• Pop the member and then push it right back
• Treat the stack as a list, check that it's not empty and if so, access stack[0]

While the latter works, it feels awkward.

How would you solve it?

I think that a peek operation that returns that member if it exists, or nothing otherwise, would be more ergonomic.

Anything else?

No response