41–50 of 138 posts
A bit of a tangent, but I tried F# recently to make a small gamedev framework. I absolutely adored the language at first. Loved the syntax. loved the type definitions and domain modeling. I felt maybe, this is it, this is the language for me. Never felt that way about a language since the last time I wrote something in Crystal. Then came the part where I needed to work with list of records and realized that something…
> " 4. Objects must always be initialized to a valid state. Not doing so is a compile-time error. " So this essentially means there can never be a NULL object assigned to anything... how is this possible? is it avoided by throwing exceptions instead of returning NULL?
No, it means that you can't leave bits off yet claim to have a valid object, either the object is fully initialised or it's illegal. This is mostly a concern in older languages like C where you can reserve space for a struct then not fill in anything.
In some more recent languages (Java, Go, C# historically though that's changing) everything is zeroed by default so you avoid the "random garbage" situation, but it means you need to assume anything can be zero even if that's not intentional, and depending on the specifics you might "double write" each location even when that's not actually necessary.
In the more functional slate of languages, you simply can't let any members off. There might be a concept of "default value" but that tends to be opt-in, the baseline is that if you define a type you must fill in every member, explicitly, before the compiler will accept it.
Initialising items to null is orthogonal.
Now since the rest is predicated on a misunderstanding I've a version of each for "incomplete initialisation" and a version for "null".
> how is [forcing complete initialisation] possible?
The compiler just requires that every member of the structure be specified.
> how is [things never being NULL] possible?
Don't make NULL an implicit member of every type.
> is [incomplete initialisation] avoided by throwing exceptions instead of returning NULL?
it's avoided by the compiler refusing to compile your code if you leave off members.
> is [things never being null] avoided by throwing exceptions instead of returning NULL?
It's avoided by NULL being a member of a completely different type than anything else, whether that type is a special case or not e.g. in Rust "null" is one member of the Option "wrapper type" so to indicate that, say, a user is optional you write `Option`, then that can either be `None` (no user, ~ null) or `Some(user)`.
If you just type something as `User` then it's necessarily a valid user and nothing else, because there is no null value you could put into it, you'd get a type error.
* Rust playground which fails to compile because one of the struct members was left off: https://play.rust-lang.org/?version=stable&mode=debug&editio...
* Rust playground which fails to compile because trying to put a null (None) in a non-nullable field: https://play.rust-lang.org/?version=stable&mode=debug&editio...
* Version of the previous with an optional (nullable) member: https://play.rust-lang.org/?version=stable&mode=debug&editio...
* Version with opt-in default (through Rust's Default trait, the default derivation of the Default trait will recursively default each field, which usually means some sort of zeroing): https://play.rust-lang.org/?version=stable&mode=debug&editio...
Speakeasy, Lightouch, Jazz is a fifth-generation programming language. I find only small hurdlesv when showing it to programmers. My challenge now is mainly getting stable shelter so I can compile these notes and hand them off to people.
I really can't work out what you're trying to say here. I can guess, but maybe it would be better if you wrote something more expository or discursive. For example, is "Speakeasy, Lightouch, Jazz" intended to be a single noun? A single thing? Or is it a collection? A sequence? What do you mean by "getting stable shelter"? Or to "hand off notes to people"? Have you written something already? is there a link?
Accessibility (as in execution environments) trumps language features in my book, and JS is the most accessible language there is. But of course, it all boils down to what you're trying to solve and where your program will live.
> I don’t care what my language will let me do, I care more about what my language won’t let me do. I think this is the best summary of the article. In short, please protect me from my own stupidity and/or laziness.
It obviously has some merit, but I'd rather have a language be an enabler rather than a disabler. And again, not having to worry about messing up is or at least can be a kind of enabler, but I prefer a more positive approach, with good defaults encouraging me to do the good and simple, but the language getting out of my way for things it might not know about.
The article goes through a series of examples to show motivations for the following: 1. Variables should not be allowed to change their type. 2. Objects containing the same values should be equal by default. 3. Comparing objects of different types is a compile-time error. 4. Objects must always be initialized to a valid state. Not doing so is a compile-time error. 5. Once created, objects and collections must be immu…
> I don’t care what my language will let me do, I care more about what my language won’t let me do. I think this is the best summary of the article. In short, please protect me from my own stupidity and/or laziness.
I like how this could be taken as an endorsement or criticism of the article, depending on the hubris of the reader
"Objects containing the same values should be equal by default." No. This breaks down as soon as you have references to other objects in your objects. If you compare by reference, you probably don't get what you want. If you compare by value, you need to go arbitrarily deep, which is not a sane default, because of possible reference cycles. You need a distinction between objects and value types. C# has that (record t…
The whole point is that equality should have nothing to do with comparing references. Your comment is just making the author's point. References, cycles, mutable state these just make it harder to reason about your code. And a nice petty little zing at the end for good measure. Good job.
If you want to define a graph data structure, cycles are inherent, so there must be some way to deal with them - they are not something that can simply be ignored. This is a completely practical problem, and identity instead of value equality is a valid answer. Of course, this doesn't contradict the original article: reference equality can still exist in the language, it just helps if it's not the default.
For example, in Common Lisp you have both `eq` (reference equality) and `equal` (typed value equality) [and even the somewhat stranger `equalp` (structural equality, e.g. (equalp '(1 2) '(1 2)) -> true)].
Speakeasy, Lightouch, Jazz is a fifth-generation programming language. I find only small hurdlesv when showing it to programmers. My challenge now is mainly getting stable shelter so I can compile these notes and hand them off to people.
I really can't work out what you're trying to say here. I can guess, but maybe it would be better if you wrote something more expository or discursive. For example, is "Speakeasy, Lightouch, Jazz" intended to be a single noun? A single thing? Or is it a collection? A sequence? What do you mean by "getting stable shelter"? Or to "hand off notes to people"? Have you written something already? is there a link?
A bit of a tangent, but I tried F# recently to make a small gamedev framework. I absolutely adored the language at first. Loved the syntax. loved the type definitions and domain modeling. I felt maybe, this is it, this is the language for me. Never felt that way about a language since the last time I wrote something in Crystal. Then came the part where I needed to work with list of records and realized that something…
Could you go into a little more detail what task you were trying to solve?
Here I ended up reading bid docs on something called Lens and was never able to apply it correctly. here is the repo i was working on https://github.com/rishavs/coral/blob/master/Engine.fs