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Functional Programming: Composition of Functions

Pratik sharma on May 15, 2021

Input of one function comes from the output of another function. 👆 simple defination of function composition that i could find. In functiona P...
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algorhymer profile image
sassenheimer •

You see... I cannot even write a technical comment - without the platform dropping it - anymore.

You know... some days ago I made a comment where I introduced the concept of Z-combinator for call-by-value languages for the author of an article.
I used that Cat from Shrek El Gato con Botas to weave it into a Zorro narrative.
Well that got deleted too.

Dev.to nowadays is sort of like a crossbreed of the movie Idiocracy and 1984.
A sort of... really heavy marketing-only, corporate, adultkindergarten.

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biomathcode profile image
Pratik sharma •

That's true to some level, I don't know why you comment got delete, maybe because of too long or similar to how youtube AI detector is not working correctly. Explaing with analogy is the best way to learn.
Software domain is just sad rn and dieing faster and i would have thought

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algorhymer profile image
sassenheimer •

You should check your Github Issues.
You have a message waiting for you.

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biomathcode profile image
Pratik sharma •

ohh thanks for the problem to solve. But i don't want to compete with ThePrimeagen.

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algorhymer profile image
sassenheimer •

Please... pretty please do it.
That guy's code can beaten from Python (vs. Rust release build, optimized).

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algorhymer profile image
sassenheimer •

@biomathcode I've been looking for a single dev for 2 years... I'm running out of Jon Snows.

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pengeszikra profile image
Peter Vivo •

Why we don't use proposal pipeline operator? Which is give composition without any library or helper function, and very useful in multiple case.

42 |> f |> g;
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Pipeline operator handy even simple log:

data |> functionForTest |> console.log;
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in react also handy this syntax sugar.

  const getTextAreaValue = ({target:{value}}) => value;
  <TextArea onChange={event => event |> getTextAreaValue |> myAction}</TextArea>
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or better

  const inputFromTextArea = action => ({target:{value}}) => value |> action;
  <TextArea onChange={myAction |> inputFromTextArea}</TextArea>
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vonheikemen profile image
Heiker •

I think there are two proposals for the pipeline operator. There is one where the operator behaves exactly like pipe() and the other proposal adds more features to it (they call it smart pipeline).

I like the idea of the simple pipeline but I imagine that a large part of the javascript community would not like such a limited feature. It would force them to learn about partial application, unary functions, and currying; in other words it would impose a specific style of programming on them. If it doesn't make their life easier they would just ignore it.

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biomathcode profile image
Pratik sharma •

Thanks to both of you! I was not aware of this new experimental pipeline operator. I like the syntax that peter has used. as per the current mozilla docs it is still in stage 1, so i don't think we can use the operator just for now. Operators have made our life easier a bit, so much time i use ? : , then using if else. I think we are moving to more simplified and less bracket world of programming.

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pengeszikra profile image
Peter Vivo •

If you would try pipeline operator, then you found in this parcel bunlder setup: github.com/Pengeszikra/react-base , react can easy remove from this.
Eslint give correct result. But one more trick for VS-Code don't show error in

"javascript.validate.enable": false,
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biomathcode profile image
Pratik sharma •

Sure will give it a try!