compile time assertions

[waalge]

Is it possible to get aiken to do a compile time assert?

// Something coming in from an ./env
const exp : Int = 5 

// Somewhere else: attempt a compile time assert on value
const is_exp_non_positive : Bool = {
    expect exp <= 0
    True
}

This doesn't work - aiken ignores this entirely.
Using is_exp_non_positive causes an ungraceful exit.

But something like this?

[KtorZ]

This isn't possible in this form at the moment. One current alternative is to use environments for it; For example you can define:

env/default.ak

pub fn assert_non_positive(n: Int) -> n {
  expect n <= 0
  n
} 

env/no-assert.ak

pub fn assert_non_positive(n: Int) -> n {
  n
} 

And in the rest of the code, use env.assert_non_positive(exp) in relevant places. You can strip out assertions using --env no-assert.

I've moved the ticket as a discussion for now. As this seem like an interesting language feature but needs to be refined and scoped accordingly before we act on it.

[waalge]

The problem with envs is it's only one at a time... i think.
As in you can only invoke one config at a time.
It is not possible to compose configs, say, preview + conservative_limits (i cant think of a good example right now).
I'm not sure i'd be a proponent for doing so cos its complexity for dimishing returns.
Namespacing is already a little magic between lib and validators. env and config (what happens if i have a config stanza and an env module with the same name ?) And i presume any env file must have the same public signatures? Splitting these makes that complicated.

So you're left with flattening envs: preview_conservative, preview_bullish, ...
which is a bit of a pain.

This is non-urgent.