> Unless we know there are data dependencies between s1 and s2 (and we don't; we're talking very abstract here)

The entire discussion is about railway programming for early exit on error handling. So yeah, there are dependencies there.

> You're purposefully twisting words here.

No. I'm pointing out you pattern matched against a generic 2-tuple in your pseudocode. There's no words to twist, returns in functions on modern hardware are atomic over 1 value in all but the most obscure languages, and it's not a new phenomenon.

If it's valid to say, "I returned 2 values" it's equally valid to say, "I returned one value and restructured it." They represent the same thing.

> And no, that's not "the type", because I was (obviously) just using straight forward pseudocode whose semantics I assumed would be intuitively clear to everyone.

Both statements can be true. I'm simply writing a type that captures your "obviously true" statements. Therefore, both are obviously true.

> There is so much hair-pulling in here and what you say is simply wrong. I was just returning two friggin' variables.

You're the one consistently lambasting folks about paying attention to what happens at the "bare metal" (ha!) level. I encourage you to take your own medicine here.

> Why do you make it seem like it was something more complicated? You must be deliberately hair-pulling just to win a stupid argument. I'm not doing any "virtual object-oriented blah blah" or any kind of types craziness.

Either you wrote something so vague it can be anything you want (e.g., your magical streams that are also not streams). If we remove the nonsensical (or I guess by your admission, non-sequitur) streams bit then you're left with this outcome. I told you exactly what I'd do in my post. You have to recognize the type of the result of each step as either a success or an error.

You've chosen to pretend none of this is about error handling, which is pretty boring IMO. Error handling is what makes code actually hard to write.

> What's wrong with my procedural code? Fill in the error handling between the steps as soon as you have a concrete instance for my abstract example.

I admit I don't know since it seems to mean exactly what you want it to, and no one else is privy to either the viewpoint nor the problem you're actually discussing. You're just here hurling vague insults about how everything other than your "obvious" pseudocode is nonsense.

> Dude, I used a pseudo-code for loop.

Not in any example I reviewed that didn't completely ignore the actual problem to burn down a straw man about streaming constructs. Also, don't call me dude. I'm not.

> I've been there and I know to use FP-ish constructs when they make sense (very rarely. Much easier to restrict to procedural altogether).

Considering you didn't recognize the product pattern match and objected vigorously to the idea that it might be as such; and tuples something nearly every statically typed FP dialect has? I gotta confess that I don't think you know the field or the techniques very well. Fair enough, many modern FP techniques in use today are less than 25 years old. No shame there. But you should probably investigate a bit more before speaking so confidently on the subject.

You really are just advocating for doing what the F# example given was doing, without all that helpful syntax or compile-time verification of correctness & totality. I dunno why you'd want that. Given that you are accidentally reusing FP pattern matches, they can't be that complicated now can they?