This is not correct. The to_something() is what throws the exception. In those languages, you need to put the try block inside the iterator's map lambda.

Again, I didn't say it was not possible in the other languages, I only stated that I didn't think it ends up being as clean (specifically in regards to C++, Java and C#)

In most languages, it is easy to write a 'try(expr, fail)' HOF that gives you the same functionality (but possibly with different performance profiles, depending on the underlying exception handling implementation).

On the other hand without non-local error handling it is harder to bail out of the outer map on a to_something error, if that's what's desired.

In Lisp the "catch" part could be "handler-bind", which could invoke a restart (skip element, or use-value). This requires the called function to establish a restart, but the good news is that it removes the burden of the decision from the innermost part.

So what, I don't care where the error occurs.

Either the full expression is successful or not.

What we are debating at this point is style. I offered something which I think is cleaner than what I see in other languages.

You don't see the point, and that's fine. Initially when Java came out with Streams I hadn't worked a lot with ETL like functions. Then while with Rust I really got it, so now I want to apply that practice to code in Java, because it simplifies many areas of code. One thing that became very clear, is that Exception handling throws a minor monkey wrench into keeping the code simple. This is why I picked the example I showed.

You don't think it's cleaner, or makes a big difference, and that's fine. I personally find it to be easier to read and create more understandable code. You can have your exceptions, but after Rust I am totally sold on the Result for errors pardigm.

I don't think it is cleaner, because usually we architect our applications in logical blocks.

For example when sending a data packet over the network and it fails, I don't care if the error was in the communication, buffer, socket level or network layer, just that the packet could not be sent.

That is what we need to retry, sending a new packet, not the lower level operations.

Languages with exceptions, which I use since 1993, allow me to choose using an exception, transform it into a plain error code or monadic error. I can have it all and choose which flavour I want to use, depending on the use case.

But as you say, it is a matter of style.