Java 8’s new Optional type doesn't solve anything

Re:Java 8’s new Optional type doesn't solve anything by valarauca1 on Tuesday October 27, 2015 @07:38AM (#10457368)

I know this but I can never get my code to compile when doing this. I always seem to get huge type errors even when I know the code is correct.

     map(|x|foo(x)) //clean compile
     map(foo) //type error

The number of times I've had this happen has just lead to me giving up on simply just passing the lambda as a variable instead of wrapping it in another.

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Re:Java 8’s new Optional type doesn't solve anything by kibwen on Tuesday October 27, 2015 @02:16PM (#10460007)

Curious. Can you provide a full code example so that I can try to determine what's causing that error?

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Re:Java 8’s new Optional type doesn't solve anything by Manishearth on Wednesday October 28, 2015 @02:20AM (#10463077)

Usually in these cases the culprit is autoderef/deref coercions.

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Re:Java 8’s new Optional type doesn't solve anything by kibwen on Thursday October 29, 2015 @12:01PM (#10472046)

I don't see anything in `|x| foo(x)` that could be causing `x` to be deref'd.

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Re:Java 8’s new Optional type doesn't solve anything by Manishearth on Friday October 30, 2015 @03:34AM (#10476545)

A deref coercion can happen there

https://github.com/Manishearth/rust-clippy/issues/116

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Re:Java 8’s new Optional type doesn't solve anything by valarauca1 on Tuesday October 27, 2015 @06:46PM (#10461731)

Just make an issue?

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Re:Java 8’s new Optional type doesn't solve anything by kibwen on Thursday October 29, 2015 @12:02PM (#10472058)

I don't think it necessarily warrants an issue on the Rust repo, this is just for my own edification.

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