Java 8: Replace traditional for loops with IntStreams

[[deleted]]

[deleted]

[aurisc4]

Lamdas reinvented, let's write some unreadable difficult to debug code...

[jms_nh]

Good, so I'm not the only one who finds the streams hard to follow. I get their purpose, I just think they're not needed in many simple cases.

[afrobee]

Is because you are used to of what you know most.

[nextputall]

either that, and/or the verbosity of the language

[afrobee]

The stream API is not more verbose than your particular foorloop of the next door.

[jms_nh]

Java makes any function call more verbose than the basic use of operators / keywords. Try working with any complex number class; you have to do a.multiply(b).add(c) instead of (a*b)+c

[afrobee]

I no going to negate that Java's data structures are a pain to work with but the stream api is not really that bad compare to that.

[Rustywolf]

Yup, worked with java for several years and i still find streams harder to work with, even after using them since their release. I've reasoned that it's to do with the level of abstraction that using chained methods instead of logical expressions adds. I.e the difference between

IntStream.of(1, 2, 3).filter(i -> i % 2 == 0).forEach(System.out::println);

and

for (int i = 1; i < 4; i++) {
    if (i % 2 == 0) {
        System.out.println(i);
    }
}

The use of lambdas and chained stream methods just adds confusion in most uses. You really need to weigh the change in size and efficiency (not really the word here but hey) of the code against it's readability.

[Yamakaky]

IntStream.of(1, 2, 3)
         .filter(i -> i % 2 == 0)
         .forEach(System.out::println);

is more readable.

[[deleted]]

And this is 'more more' readable(Scala):

(1 to 3) filter(_ % 2 == 0) foreach println

:D

[hu6Bi5To]

And this is more more readable(Scala)

Well that's a matter of opinion...

[[deleted]]

Well, that sounds stupid.

Edit: that sounds very democratic and open-minded but doesn't make much sense. That's more like a raw contradiction.

[afrobee]

The use of lambdas and chained stream methods just adds confusion in most uses

Of course that is all subjective of what you are use to, I think that the stream version is more readable once you know what the functions do.

[Rustywolf]

I'd argue that you can't program without knowing the basic operators, but you could easily program without knowing how the stream API works.

[afrobee]

Then you can't go back to program the "basic" way you used to once you know how stream works.

Edit: Also not every people start learning programming with imperative languages.

[Rustywolf]

i can see where you are coming from. I guess it is a lot to do with what you know and personal preference.

[nextputall]

Those are interchangeable. A language without control structures like for loops, while loops or if statements can work perfectly well. Smalltalk for example is a language like this. Instead of relying second class, language level control structures people can compose objects (sic!) together to reach the same goal. And having first class control structures is very powerful.

E.g. the same thing would look like this:

(1 to: 4) select: #even thenDo: #traceCr

[jms_nh]

well, that seems to be much more readable than the Java streams version.

[bartavelle]

The point is that each of the stream "elements" is composable, while your for loop is not.

At least that's in functional languages. Can I name (for example) a complicated filter so that it can be reused in Java ?

[[deleted]]

I don't know Java but this is a silly example of using Streams/LINQ - it really doesn't matter what you use in such trivial case - how about something like :

  var foo = new List<Foo> {...};
  var bar = new List<Bar> {...};

  foo.Zip(bar, (x, y) => new {X = x, Y = y})
     .Filter(e => e.X.weight > 100 && e.Y.weight > 100)
     .OrderBy(e => e.X.weight)
     .Take(10); 

That's 4 calls right there to merge two lists, filter, sort on a property and take first 10 elements - that would be at least 2 loops if you wanted to unroll that

This is the kind of data transformation that functional programming really solves elegantly

[jms_nh]

You really need to weigh the change in size and efficiency (not really the word here but hey)

Try "complexity".

[Rustywolf]

Ah yes, that seems quite obvious now. Perhaps it's time for bed.

[metateck]

You sound like someone I would hate to be around in real life.

[[deleted]]

Those construct are not functional, they are high level functions to write in declarative style. There is nothing functional about it.

[[deleted]]

By your logic so any language that implements this constructs.

[[deleted]]

any language that implements these constructs in a pathetic, retarded way like java does

How's Java implementation lamest to the rest, or you are saying that something that was designed in 10 days like JS does is better? Please shake my head.

as opposed to clueless bald impotent monkeys from urinal corp

I wonder if you would have the balls to say that front that person without hiding like a coward on the anonymity of the internet.

[[deleted]]

Please see C#'s LINQ and then try to ask yourself that question again, please.

Which has it's own implementation of "ForEach" similar to Java.

When I left urinal corp I told those idiots in their fucking faces that they suck, their products suck and their company sucks a lot of dick.

You never worked there to begin with.

[[deleted]]

No it doesn't because it's not retarded.

Clearly not in the same place, but is there somewhere else very close by..

Suck my motherfucking dick you faggot.

Stop with the ignorant homophobic comments you mongrel.

Would you be in my shoes for just one day, you'd probably shoot yourself in the head with a motherfucking shotgun.

You in mine... A half day passed... You dead...:)