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  • k

    karelpeeters

    03/06/2018, 1:46 PM
    eg. 
    map.keys
    doesn't return
    a [MutableSet] of all keys in this map.
  • k

    karelpeeters

    03/06/2018, 1:47 PM
    And how would 
    containsValue
    even be implemented?
    Returns true if this map maps one or more keys to the specified value.
  • k

    karelpeeters

    03/06/2018, 1:48 PM
    What if all of the possible instances of the key type are already real keys in the map and so the map doesn't necessarily contain the default value?
  • k

    karelpeeters

    03/06/2018, 1:51 PM
    I'm having some problems with delegation:
    Copy code
    class Test<K, V>(map: MutableMap<K, V>): MutableMap<K, V> by map

val test = Test(mutableMapOf(1 to "hello"))
test[1] += " there"
    results in an exception at runtime:
    Copy code
    Exception in thread "main" java.lang.IllegalAccessError: tried to access method kotlin.collections.MapsKt__MapsKt.set(Ljava/util/Map;Ljava/lang/Object;Ljava/lang/Object;)V from class BugKt
	at BugKt.main(Bug.kt:6)
  • h

    hho

    03/06/2018, 1:56 PM
    if you change the example to an 
    <Int, Int>
    map it doesn't compile anymore... That smells like a bug.
  • h

    hho

    03/06/2018, 1:58 PM
    produces the nullability error which started our discussion
    -.kt
  • k

    karelpeeters

    03/06/2018, 2:03 PM
    @hho Huh that's right, that should not be allowed to compile at all because of the nullability.
  • k

    karelpeeters

    03/06/2018, 2:03 PM
    I'll report it on YouTrack.
  • k

    karelpeeters

    03/06/2018, 2:06 PM
    Ah no it can compile because 
    null + "test"
    is okay.
    👀 1
  • k

    karelpeeters

    03/06/2018, 2:07 PM
  • g

    ghosalmartin

    03/06/2018, 3:15 PM
    anyone know how I can iterate over a float range
  • p

    poohbar

    03/06/2018, 3:17 PM
    In a math sense that range would be inifinite.
  • p

    poohbar

    03/06/2018, 3:18 PM
    In a java sense it would still not be what you want
  • j

    jw

    03/06/2018, 3:18 PM
    you could get the bounds and then iterate with bits at the precision of the host language/VM
  • p

    poohbar

    03/06/2018, 3:19 PM
    you could but should you?
  • j

    jw

    03/06/2018, 3:19 PM
    nope!
  • b

    Benoît

    03/06/2018, 3:19 PM
    Basically the question is how can we convert this Java code to Kotlin:
    Copy code
    for(float i = 0f ; i < 1f ; i+=0.1f){

}
  • j

    jw

    03/06/2018, 3:20 PM
    unless you're testing some algorithm, then there's little reason not to iterate over the entire valid set of inputs
  • p

    poohbar

    03/06/2018, 3:20 PM
    that's not iterating over a float range
  • k

    karelpeeters

    03/06/2018, 3:21 PM
    What about
    Copy code
    for (i in 0 until 10) {
    val f = i / 10f
    ...
}
  • p

    poohbar

    03/06/2018, 3:22 PM
    Copy code
    List(10) { it / 10.0 }.forEach { 
            
}
    🤮 1
    😞 1
  • k

    karelpeeters

    03/06/2018, 3:22 PM
    At least least make it a sequence...
  • p

    poohbar

    03/06/2018, 3:22 PM
    maybe I would just go with a while loop
  • b

    Benoît

    03/06/2018, 3:23 PM
    The problem is that 10 is a magic number in that code and it sometimes doesn't work for me cause the steps should be able to be as small as needed
  • p

    Pere Casafont

    03/06/2018, 3:23 PM
    using a float as loop control "counter" is a smell already
  • p

    Pere Casafont

    03/06/2018, 3:24 PM
    make that 10 be 
    1f / step
  • p

    Pere Casafont

    03/06/2018, 3:24 PM
    and fixed
  • k

    karelpeeters

    03/06/2018, 3:24 PM
    10 is a magic number
    It's exactly as magic as 
    0.1
    .
  • p

    poohbar

    03/06/2018, 3:24 PM
    👆
  • b

    Benoît

    03/06/2018, 3:24 PM
    @Pere Casafont I have to work with values between 0 and 1
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