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- k
karelpeeters
10/21/2017, 1:56 PMAre you using a build tool? - d
Daniel Illescas
10/21/2017, 1:56 PMI don’t think so - k
karelpeeters
10/21/2017, 2:00 PMThen where did you add it as a dependency to you project? What idea plugin are you talking about? - d
Daniel Illescas
10/21/2017, 2:00 PM@Daniel Illescas uploaded a file:Pasted image at 2017-10-21, 4:00 PM▾
- d
Daniel Illescas
10/21/2017, 2:11 PMnevermind, I just needed to import the dependency to the maven project (I’ve never used this before…) - k
karelpeeters
10/21/2017, 2:23 PMYea the idea plugin isn't required I think, and it isn't enough to make the code compile. - k
karelpeeters
10/21/2017, 2:23 PMAlso maven would be an example of a build tool. - d
Daniel Illescas
10/21/2017, 2:26 PMyes - m
Marc Knaup
10/21/2017, 3:29 PMHow can I get the Java Class object for boxed primitives in Kotlin? 😮 And does Kotlin have a utility method which allows me to use
with auto-boxing in mind? (i.e. here Int<>int are assignable to each other).Class.isAssignableFrom - o
oday
10/21/2017, 3:33 PManyone know a plugin for IntelliJ that displays the shortcuts as a tooltip as they’re being used? - o
oday
10/21/2017, 3:33 PMfor screen casting - s
selckin
10/21/2017, 3:33 PMkeypromoter - s
selckin
10/21/2017, 3:34 PMno thats the other way maybe - o
oday
10/21/2017, 3:35 PMpresentatio nassistant maybe - o
oday
10/21/2017, 3:35 PM - o
oday
10/21/2017, 3:35 PMyep - d
Don Raul
10/21/2017, 4:42 PMshouldn'tCopy code
compile?fun<T, U> MutableList<T>.mapInPlace(f: (T) -> U): MutableList<U> = (this as MutableList<U>).apply { for (i in (0..size)) { val t: T = this@mapInPlace[i] this@apply[i] = f(t) } } - k
karelpeeters
10/21/2017, 4:44 PMWell no, because while looping over it you've already cast to
.U - d
Don Raul
10/21/2017, 4:44 PMso
should be anthis@mapInPlace[i]
?U - k
karelpeeters
10/21/2017, 4:45 PMI think so, yes. The compiler has something called "smart casts", cast information can sometimes be retained. - d
Don Raul
10/21/2017, 4:46 PMMkay, i thought that this@mapInPlace was would refer to a MutabelList<T> - d
Don Raul
10/21/2017, 4:47 PMand this@apply is the casted MutableList<U> - k
karelpeeters
10/21/2017, 4:47 PMThis function is a terrible idea btw:Copy codeval list = mutableListOf(1, 2, 3) list.mapInPlace(Int::toString) val minusOne = -list[0] //runtime error - d
Don Raul
10/21/2017, 4:48 PMYeah , the semantics are questionable - d
Don Raul
10/21/2017, 4:48 PMwhat im asking in what this@mapInPlace should refere to - d
Don Raul
10/21/2017, 4:49 PMSince mapInPlace is a extension on List<T>, it seems reasoable that this@mapInPlace referes to List<T>. - k
karelpeeters
10/21/2017, 4:49 PMAfter a cast the perceived type of a variable changes:Copy codefun foo(a: Any) { a as String println(a.reverse()) //a is String now } - d
Don Raul
10/21/2017, 4:49 PMDid not read the spec though. - d
Don Raul
10/21/2017, 4:50 PM``` - d
Don Raul
10/21/2017, 4:50 PMCopy codefun<T, U> MutableList<T>.mapInPlace(f: (T) -> U): MutableList<U> { val theze = this return (this as MutableList<U>).apply { for (i in (0..size)) { val t: T = theze[i] this@apply[i] = f(t) } } }