I've this codesnippet:
val O = Array(3, "str")
for (o <- O) print(o)
println("\n===")
for (_ <- O) print(_)
println("\n===")
It prints
3str
===
===
Why the second for+print(_) doesn't print anything? Any explanations?
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Hind Forsum
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use for (_ <- O) print(\`_\`) you will get the expected result – Puneeth Reddy V Nov 07 '18 at 09:45
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Alternatively, use `O.foreach(print)` (or `O.foreach(print(_))` or `O.foreach(x => print(x))`) – James Whiteley Nov 07 '18 at 13:12
1 Answers
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for (_ <- O) translation: Pull each element from O but don't assign them to anything. Just throw those values away.
print(_) translation: For each unused element from O, use eta expansion to turn the print() method into a proper function that does the same thing. Then throw it away.
Added reference: What are all the uses of an underscore in Scala?
jwvh
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