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Discovered what appears to be a bug with the `in` ...
# kotlin-native
n
Discovered what appears to be a bug with the 
in
operator. Below is some sample code from a prototype which doesn't work as expected if the 
dataType
argument contains one or more space characters (eg " kotlin.String "):
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fun processDataType(dataType: String): String {
    val kotlinBaseTypes = setOf("<http://kotlin.Int|kotlin.Int>", "kotlin.String", "kotlin.UInt")
    return if (dataType in kotlinBaseTypes) dataType.trim().replace("kotlin.", "")
    else dataType.trim()
}
I'm wondering if the issue is limited to Kotlin Native or if it affects other Kotlin platforms. Replacing
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return if (dataType in kotlinBaseTypes) dataType.trim().replace("kotlin.", "")
with
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return if (dataType.trim() in kotlinBaseTypes) dataType.trim().replace("kotlin.", "")
works around the issue.
e
how is that a bug? containers always work that way
r
You seem surprised that 
"kotlin.String"
and 
" kotlin.String "
are not the same strings, there's no bug here
n
Why does the 
in
operator have to match the entire String? Positional matches should be covered by the 
in
operator. Provided the text being matched exists in the String, the position shouldn't matter.
e
Copy code
x in container
is equivalent to
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container.contains(x)
that always means
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container.any { it == x }
not
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container.any { it.contains(x) }
👍 1
it couldn't possibly work any other way, 
container
could be any type of container, such as 
List<Int>
, and 
int
and 
Int
definitely doesn't have a `in`/`contains`
n
That explains why the 
in
operator doesn't behave the same way as the 
contains
function.
e
no, the 
in
operator behaves the exact same way as the 
contains
function, the order of arguments is just reversed
❓ 1
image.png
n
Is there a function in the Kotlin std lib that can do text matching, where the position in the String doesn't matter?
e
no
if you want to write 
kotlinBaseTypes.any { it in dataType }
then just do that
it makes no sense to do that with a 
Set
though
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