DevoxxUK Lambdas Lab

Richard Warburton richard.warburton at
Thu Apr 4 02:04:30 PDT 2013

>   Stream<Integer> s = Arrays.asList(1, 2, 3, 4).stream();
>   IntStream is = s.mapToInt(Integer::intValue);
> Things have been moving fast so i don't know if the lambda build you used
> had the overloaded map methods or map/mapToInt etc.

We were using b82, which has a map function with overloads on primitive
Functional Interfaces.

Thanks for clarifying the correct idiom.  For the record I saw several
people do something like:

ToDoubleFunction toDouble = d -> (double) d;
DoubleStream ds =;


  Richard Warburton
  @RichardWarburto <>

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