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Lambda expression comparison between C++11, C++14 and C++17

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Re: Lambda expression comparison between C++11, C++14 and C++17

#3

Post by frozenport »

jaytaylor wrote: post #2

This is the first time I've looked at C++ lambdas. They appear magnificently powerful and also like another pile of easy ways to get completely screwed up. Ah well, that's just the C++ way I suppose. Makes me glad for Rust, that's for sure!

What do you mean? Only time you can mess up a lambda is if a pointer that you're using gets changed. And this kind of dupicate ownership is a general problem with pointers.

Re: Lambda expression comparison between C++11, C++14 and C++17

#4

Post by vvanders »

frozenport wrote: post #3
jaytaylor wrote: post #2

This is the first time I've looked at C++ lambdas. They appear magnificently powerful and also like another pile of easy ways to get completely screwed up. Ah well, that's just the C++ way I suppose. Makes me glad for Rust, that's for sure!

What do you mean? Only time you can mess up a lambda is if a pointer that you're using gets changed. And this kind of dupicate ownership is a general problem with pointers.

Yeah, I'm not following as well. I've used Lambdas in C++ pretty heavily and they're really well done and thought out.

FWIW nothing about them is much different from Rust's approach(anon struct + fn) it's all the ownership guarantees which give Rust it's safety.

Re: Lambda expression comparison between C++11, C++14 and C++17

#5

Post by jguegant »

jaytaylor wrote: post #2

This is the first time I've looked at C++ lambdas. They appear magnificently powerful and also like another pile of easy ways to get completely screwed up. Ah well, that's just the C++ way I suppose. Makes me glad for Rust, that's for sure!

Here take your rustwin point!

I really like the explicit capture of C++'s lambdas more than the implicit one in most other languages (C#, Java, Python...) where you easily ends-up with a closure not referencing the expected variable. See: https://blogs.msdn.microsoft.com/ericlippert/2009/11/12/clos...

Re: Lambda expression comparison between C++11, C++14 and C++17

#6

Post by rileymat2 »

frozenport wrote: post #3
jaytaylor wrote: post #2

This is the first time I've looked at C++ lambdas. They appear magnificently powerful and also like another pile of easy ways to get completely screwed up. Ah well, that's just the C++ way I suppose. Makes me glad for Rust, that's for sure!

What do you mean? Only time you can mess up a lambda is if a pointer that you're using gets changed. And this kind of dupicate ownership is a general problem with pointers.

I think you have issues with reference capture groups and object lifetimes. Or alternatively value capture groups and object slicing.

Re: Lambda expression comparison between C++11, C++14 and C++17

#8

Post by [deleted] »

jguegant wrote: post #5
jaytaylor wrote: post #2

This is the first time I've looked at C++ lambdas. They appear magnificently powerful and also like another pile of easy ways to get completely screwed up. Ah well, that's just the C++ way I suppose. Makes me glad for Rust, that's for sure!

Here take your rustwin point! I really like the explicit capture of C++'s lambdas more than the implicit one in most other languages (C#, Java, Python...) where you easily ends-up with a closure not referencing the expected variable. See: https://blogs.msdn.microsoft.com/ericlippert/2009/11/12/clos...

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