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Schema for Clojure(Script) Data Shape Declaration and Validation

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Re: Schema for Clojure(Script) Data Shape Declaration and Validation

#51

Post by w01fe »

jwr wrote: post #37
w01fe wrote: post #16

Earlier quoted context omitted.

Thanks for the feedback! Actually, schema can express arbitrary constraints. Your example translates to schema as: {String {(s/required-key "product") [String] (s/required-key "type") (s/enum "type1" "type2") s/Any s/Any}} ;; allow any other k-v pairs

Interesting! Is the enum automatically a vector/sequence, or is that just an omission in the example? Looks like I'll be using this library sooner than I thought, thanks!

Nope, I missed that in the example -- the enum should be in square brackets.

Re: Schema for Clojure(Script) Data Shape Declaration and Validation

#52

Post by w01fe »

ambrosebs wrote: post #42

core.typed author here. It might be easy to consider Schema as "competitor" to core.typed. In fact, it's the opposite: once they play nicely together they will form a formidable bug-fighting, finely-documenting team. :) core.typed has accurate compile time checking, and Schema gives an expressive contracts interface for runtime checking. Once they understand each other, you can start pushing and pulling between stati…

I've been really pumped about core.typed since I first heard about it, and I'm excited about the possibilities of combining (or eventually replacing) schema with core.typed.

I think core.typed has come a long way since last time I looked at it (when we started developing schema). Obviously it's a much bigger and more serious effort, and schema was about getting as much bang right away as we could for a few bucks.

I'd love to talk in more detail about how we can collaborate, or at least make sure we play nice together.

Re: Schema for Clojure(Script) Data Shape Declaration and Validation

#53

Post by w01fe »

JackMorgan wrote: post #44

What timing! I have been making this exact thing myself. Would you be interested in pull requests making your api simpler? Maybe allow parameters to not have to have shapes? Perhaps allowing a syntax that allows a simple way to shapes in the meta alongside the ability to change the signature for people who don't want to couple too tightly to the library? When I showed mine to my local user group last month, that was…

Sure, we're happy to consider pull requests.

Schemas are already optional -- you can have a s/defn with no, some, or full schematization. You can also put the schemas in the meta if you don't like the :- syntax. I'm not quite sure what you mean by the other point though. My email is in my profile, let's talk :)

Re: Schema for Clojure(Script) Data Shape Declaration and Validation

#54

Post by w01fe »

JackMorgan wrote: post #45
JackMorgan wrote: post #44

What timing! I have been making this exact thing myself. Would you be interested in pull requests making your api simpler? Maybe allow parameters to not have to have shapes? Perhaps allowing a syntax that allows a simple way to shapes in the meta alongside the ability to change the signature for people who don't want to couple too tightly to the library? When I showed mine to my local user group last month, that was…

Also, what about having your defn macro generate a second function like foo-t that just calls with-fn-validation on foo, to clean up that extra call? Would you be interested in such a pull request?

I'd have to think about that a bit -- I'm hesitant to create names not provided by the user, but maybe there is another way.

Quite honestly that part of things (turning validation on and off, etc) isn't really done yet -- we have plans to make it much more flexible and powerful, but haven't got there yet.

Re: Schema for Clojure(Script) Data Shape Declaration and Validation

#55

Post by ambrosebs »

w01fe wrote: post #49
ambrosebs wrote: post #38

Earlier quoted context omitted.

Author of core.typed here. I will challenge that schemas are "significantly" better for documentation than core.typed types. With unions, intersections, heterogeneous maps, parameterised classes, recursive types we can be very expressive. Here's some examples of the syntax for types: https://github.com/clojure/core.typed/wiki/Types And some declarative types in action: https://github.com/frenchy64/core.typed-example/…

Sorry, that didn't come across the way I wanted -- it certainly wasn't meant as a dig on the expressiveness or power of core.typed, which is a project I'm really excited about. The main driver for Schema was to make annotating function inputs and outputs as simple and readable as possible. Personally, I find annotations directly on the function arguments easier to parse than separate function type declarations, but I…

No problem, just was eager to clarify :)

FWIW there are macros like fn> that allow you to write (fn> :- Number [a :- Symbol] 1), but you lose the ability to write ordered function types with multiple cases, so I don't use it very much.

Re: Schema for Clojure(Script) Data Shape Declaration and Validation

#56

Post by ambrosebs »

w01fe wrote: post #52
ambrosebs wrote: post #42

core.typed author here. It might be easy to consider Schema as "competitor" to core.typed. In fact, it's the opposite: once they play nicely together they will form a formidable bug-fighting, finely-documenting team. :) core.typed has accurate compile time checking, and Schema gives an expressive contracts interface for runtime checking. Once they understand each other, you can start pushing and pulling between stati…

I've been really pumped about core.typed since I first heard about it, and I'm excited about the possibilities of combining (or eventually replacing) schema with core.typed. I think core.typed has come a long way since last time I looked at it (when we started developing schema). Obviously it's a much bigger and more serious effort, and schema was about getting as much bang right away as we could for a few bucks. I'd…

Fantastic, bring it on!

Re: Schema for Clojure(Script) Data Shape Declaration and Validation

#58

Post by AlexBaranosky »

ambrosebs wrote: post #56
w01fe wrote: post #52

Earlier quoted context omitted.

I've been really pumped about core.typed since I first heard about it, and I'm excited about the possibilities of combining (or eventually replacing) schema with core.typed. I think core.typed has come a long way since last time I looked at it (when we started developing schema). Obviously it's a much bigger and more serious effort, and schema was about getting as much bang right away as we could for a few bucks. I'd…

Fantastic, bring it on!

I wonder if there's some way to combine schema, core.typed and clj-schema in some way that is better than the sum of its parts. (https://github.com/runa-dev/clj-schema)

I regrettably haven't had much time to see where the cross-section between these libraries is exactly, being very occupied at work. But I'd rather work on one grand thing, than end up with disparate libraries that aren't as fully-featured.

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