What is the equivalent lambda expression for System.out::println

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The method reference System.out::println will evaluate System.out first, then create the equivalent of a lambda expression which captures the evaluated value. Usually, you would use
o -> System.out.println(o) to achieve the same as the method reference, but this lambda expression will evaluate System.out each time the method will be called.

So an exact equivalent would be:

PrintStream p = Objects.requireNonNull(System.out);
numbers.forEach(o -> p.println(o));

which will make a difference if someone invokes System.setOut(…); in-between.

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