Hello World as first exercise - is it OK to introduce Option so early?

[petertseng]

Hello World is our first exercise. It introduces Options.

exercism/problem-specifications#290 (comment)

Ian said it best:

Some/None. Really? We did that in Hello World?

Is it too much of a hurdle for students to get over, or are students usually good enough at looking up https://doc.rust-lang.org/std/option/ that they can figure it out?

If anyone has evidence to share one way or the other, I'd be pleased if you could help by sharing it. I'd also like to know because the Haskell track also wants to add hello-world (exercism/haskell#475)

[petertseng]

Question you might ask: "If we for some reason decided to remove hello world, when would Option be introduced again?"

I believe the answer is when we use Result in hamming. Not exactly Option, but close enough.

[ErikSchierboom]

Speaking for myself, I think I'd be rather confused if hello-world would be the first exercise. Options are not that difficult, but leap for example is easier I believe. But then again, I'm perhaps not the average Haskell programmer.

[petertseng]

If anyone has evidence

Well, uh, I have stats? Here are some languages that either do or could ostensibly use option/maybe/non-nullable reference types/whatever analogous concept in their hello world tests:

Do not have hello world:

• http://exercism.io/stats/haskell (would use Maybe)

Have hello world:

• http://exercism.io/stats/elm (uses Maybe)
• http://exercism.io/stats/fsharp (uses option)
• http://exercism.io/stats/kotlin (NB: uses both non-nullables and default argument)
• http://exercism.io/stats/ocaml (uses option)
• http://exercism.io/stats/rust (uses Option)

For the following tracks, including their stats in the comparison would not be a direct comparison against the above languages because:

• ceylon (would use non-nullables, but this track is not active)
• crystal (types are non-nullable, but they use default arguments in their hello-world)
• scala (has Option, but all reference types are still nullable, and uses default arguments in hello-world)
• swift (types are non-nullable, but they use default arguments in their hello-world)

You know what? I honestly don't know if there are interesting insights to be gained from these stats, but I'll post them here anyway in case anyone does see anything interesting!

[ErikSchierboom]

The F# track also uses optional values.

[petertseng]

Embarrassing that I forgot it. Added to list.

---

I also didn't realize so many languages were doing this. Maybe I should have asked in a more general place, rather than the Rust track. I only knew that Rust was using option, and didn't do my research to see that other tracks were as well.

[petertseng]

We can talk about this in exercism/problem-specifications#520

by the way I missed purescript - they also use option.