Denis Zharkov
56477f0af8
Load immutable flexible upper bound for 'Iterable<? super T>' We load 'Collection<? super CharSequence>' as 'MutableCollection<in CharSequence>' instead of 'MutableCollection<in CharSequence>..Collection<*>' because it's obviously not typesafe to use any 'Collection<*>' as argument for such type. But there'se nothing bad with loading 'Iterable<? super CharSequence>' as 'MutableIterable<*>..Collection<*>'. Same for other declarations that have covariant mutable representation (currently Iterator, ListIterator). Also there are useful use-cases when it's neccessary to use 'Iterable<*>' as an argument for parameter with type 'Iterable<? super T>' (see matchers.kt test). NB: Star-projections appear in examples because types like 'Collection<in CharSequence>' with conflicting use-site projections are invalid in Kotlin, but they are valid in Java.
19 lines
384 B
Kotlin
Vendored
19 lines
384 B
Kotlin
Vendored
// FILE: Assert.java
|
|
|
|
public class Assert {
|
|
public static <T> void assertThat(T actual, Matcher<? super T> matcher) {
|
|
}
|
|
}
|
|
|
|
// FILE: Matcher.java
|
|
public class Matcher<T> {
|
|
public static <T> Matcher<java.lang.Iterable<? super T>> hasItem(T item) {
|
|
return null;
|
|
}
|
|
}
|
|
|
|
// FILE: main.kt
|
|
fun test(x: List<String>) {
|
|
Assert.assertThat(x, Matcher.hasItem("abc"))
|
|
}
|