Rock-Solid JavaScript through Applied Science

Many of our Java application have JavaScript frontends. While the Java part of the application is considered to be well engineered, the JavaScript part often lacks industrial-strength stability. This talk shows new ways to make your JavaScript code more reliable - not by introducing new frameworks or libraries but by doing less, going back to the basics, and leveraging the science behind the lambda calculus.

Transcript

1. www.karakun.com Rock-solid JavaScript through Applied Science Prof. Dierk König
2. 2 Dierk König Fellow at Karakun Prof at FHNW @mittie @ProfDKoenig https://dierk.github.io/Home
3. 3 Oxymoron JavaScript and Rock-solid JavaScript and Applied Science
4. 4 Computability Turing Machine Lambda Calculus Recursive Functions
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   5FSNT // atoms const id = x => x; const fst = x => y => x; const snd = x => y => y;
10. 1BJS // atoms const id = x => x; const fst = x => y => x; const snd = x => y => y; const Pair = x => y => accessor => accessor(x)(y);
11. 1BJS
    $SFBUJPO // atoms const id = x => x; const fst = x => y => x; const snd = x => y => y; const Pair = x => y => accessor => accessor(x)(y); const point = Pair(1024)(200);
12. 1BJS
    "DDFTT // atoms const id = x => x; const fst = x => y => x; const snd = x => y => y; const Pair = x => y => accessor => accessor(x)(y); const point = Pair(1024)(200); point(fst); // 1024, compare to pair.fst point(snd); // 200, compare to pair.snd the basic product type
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    4VN const Left = x => f => g => f(x); // ctor 1 const Right = x => f => g => g(x); // ctor 2 const either = e => f => g => e(f)(g); // accessor const safeDiv = x => y => y === 0 ? Left ("divisor is zero") : Right(x / y); either ( safeDiv(1)(0) ) ( msg => console.log(msg) ) ( res => id(res) ) η-reduce
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    "MHFCSB const Left = x => f => g => f(x); // ctor 1 const Right = x => f => g => g(x); // ctor 2 const either = e => f => g => e(f)(g); // accessor const safeDiv = x => y => y === 0 ? Left ("divisor is zero") : Right(x / y); either ( safeDiv(1)(0) ) ( console.log ) ( id ) η-reduce
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20. &JUIFS
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    4VN const Left = x => f => g => f(x); // ctor 1 const Right = x => f => g => g(x); // ctor 2 const either = id ; // accessor const safeDiv = x => y => y === 0 ? Left ("divisor is zero") : Right(x / y); either ( safeDiv(1)(0) ) ( console.log ) ( id )
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    0QUJPOT const [Cash, CreditCard, Transfer, match] = Choice(3); // generalized sum type const pay = payment => match(payment) ( () => amount => 'pay ' + amount + ' cash') ( ( { number, sec } ) => amount => 'pay ' + amount + ' with credit card ' + number + ' / ' + sec) ( ( [ from, to ] ) => amount => 'pay ' + amount + ' by wire from ' + from + ' to ' + to); let payment = Cash(); assert.is( pay(payment)(50), 'pay 50 cash'); payment = CreditCard( { number: '0000 1111 2222 3333', sec: '123' } ); assert.is( pay(payment)(50), 'pay 50 with credit card 0000 1111 2222 3333 / 123'); payment = Transfer(['Account 1', 'Account 2']); assert.is( pay(payment)(50), 'pay 50 by wire from Account 1 to Account 2');
24. 24 Rock-solid Science Rock-solid immutable "Objects" Null-safe operations that cover all cases All done with lambda expressions
25. 25 Repository https://github.com/Dierk/ BrushUpYourJavaScript
26. 26 Credits Gabriel Lebec @g_lebec Daniel Dietrich @danieldietrich
27. 27 Further Support Engineering, Consulting, Training Certificate of Advanced Studies
28. Karakun AG Elisabethenanlage 25 4051 Basel Switzerland T. E. W. +41 61 551 36 36 info@karakun.com www.karakun.com Gerne beraten und schulen wir auch Sie dabei, welche Technologien sie am besten einsetzen und wie sie ihre Software-Entwicklung verbessern können. Wir freuen uns auf Ihre Kontaktaufnahme!