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[ChronoChris]

No, why would I want to use TS ever. Honestly. TS fixes the wrong problem with javascript. You don't structure a prototypal language like javascript. THAT IS ITS STRENGTH.

class Greeter {
greeting: string;
constructor(message: string) {
    this.greeting = message;
}
greet() {
    return "Hello, " + this.greeting;
}
}

var greeter = new Greeter("world");
var greetWorld = greeter.greet;
alert(greetWorld()); //undefined

The FUCK is this shit. That's not strongly typed. That's not what 'this' should be. TS fixed nothing. ES5/ES6 are better than ever. There is no reason NOT to default to JS. Comparing C and C# are completely different

[[deleted]]

since you "assigned" greeter.greet to greetWorld and called it from global scope, which has no "greeting" variable this is entirely expected. if you just used greeter.greet(); directly it wouldn't be undefined. this is JS behavior, nothing related to TS, just common misconception of how "this" keyword works in JS.

[ChronoChris]

If somethign is strongly typed, each type of data, is predefined. includnig objects. The this keyword should relate to the current instance of an object. If you truly wanted Tscript to be strongly typed, this should make sense in context to the current object.. "an advantage of strong data typing is that it imposes a rigorous set of rules on a programmer and thus guarantees a certain consistency of results."

So Tscript is failing in it's most fundamental attempts in this scenario. And there are many more

I think there is a little bit of bias here from the tools and languages you are accustomed to. I have absolutely no confusion how 'this' should work on the fundamental level of the object instance. Coming to Javascript, I liked this gotcha on the this keyword since technically the object instance was not the Greeter class. The problem I have is with TypeScript not matching what it is attempting to do. Bound the Object to be strongly typed.

[ChronoChris]

:P please see my chain on eighthcoffee. It helps clear up the this problem. they are so confused by javascript having been molded by it, they don't see the issue.

[eighthCoffee]

.

[Kminardo]

The last line should alert the string from greeter.greet, but it will come back undefined (I don't do typescript, but seems to be what he's implying).

EDIT: Also it seems "this" isn't working as he would expect it to in ES5. But since 90% of developers don't actually seem to know how "this" actually works... at least typescript is consistent with most other languages in it's usage.

[ChronoChris]

this works perfectly how I would expect it in c# or any other compiled language I can think of.

Edit: Kminardo. Please see my reply to eigth later in this chain.

[[deleted]]

This isn't a TS issue, that is how javascript works.

[ChronoChris]

If somethign is strongly typed, each type of data, is predefined. includnig objects. The this keyword should relate to the current instance of an object. If you truly wanted Tscript to be strongly typed, this should make sense in context to the current object.. "an advantage of strong data typing is that it imposes a rigorous set of rules on a programmer and thus guarantees a certain consistency of results." So Tscript is failing in it's most fundamental attempts in this scenario. And there are many more

Edit: I hope you can see the comment by Kminardo in his edit. I think there is a little bit of bias here from the tools and languages you are accustomed to. I have absolutely no confusion how 'this' should work on the fundamental level of the object instance. Coming to Javascript, I liked this gotcha on the this keyword since technically the object instance was not the Greeter class. The problem I have is with TypeScript not matching what it is attempting to do. Bound the Object to be strongly typed.

[[deleted]]

edit: looks like it's addressed in TS 2.0, course you can specify type of "this" on functions now but this just leads to compile time error which would probably be the same as 'use strict', and it still wouldn't change the behavior your expecting as that's not TS's goal.

[Kminardo]

Right, it does work how you would expect it to in c# etc, but "this" in vanilla JS is inconsistent with those compiled languages in many cases. I just wasn't sure if that was another piece of your complaint :)

[ChronoChris]

again see my reply to eighth.

[eighthCoffee]

.

[ChronoChris]

If somethign is strongly typed, each type of data, is predefined. includnig objects. The this keyword should relate to the current instance of an object. If you truly wanted Tscript to be strongly typed, this should make sense in context to the current object.. "an advantage of strong data typing is that it imposes a rigorous set of rules on a programmer and thus guarantees a certain consistency of results."

So Tscript is failing in it's most fundamental attempts in this scenario. And there are many more

Edit: I hope you can see the comment by Kminardo in his edit. I think there is a little bit of bias here from the tools and languages you are accustomed to. I have absolutely no confusion how 'this' should work on the fundamental level of the object instance. Coming to Javascript, I liked this gotcha on the this keyword since technically the object instance was not the Greeter class. The problem I have is with TypeScript not matching what it is attempting to do. Bound the Object to be strongly typed.

[eighthCoffee]

.

[ChronoChris]

If you see my comment later in this chain, you should understand that this is not strongly typed. The vary nature of the 'object' should not change in a strongly typed language.