[doc] Try/catch are no longer Experimental. Possible clarification in perlsyn

[lindleyw]

Where
Perlfunc outdated; and suggestion in perlsyn to clarify how a finally block differs from code that merely follows try/catch.

Description
The documentation for try/catch/finally in perlfunc still (as of v5.42.0) refer to "the experimental try feature". It is no longer experimental.

Also: In perlsyn, where it states:

The finally block is equivalent to using a defer block and will be invoked in the same situations; whether the try block completes successfully, throws an exception, or transfers control elsewhere by using return, a loop control, or goto.

perhaps more bluntly clarify why one might use a finally block, perhaps as:

The finally block is equivalent to using a defer block and will be invoked in the same situations: not only when the try block completes successfully or throws an exception, but also (out of the ordinary order of execution) immediately before code in the try or catch blocks transfers control elsewhere by using return, a loop control, or goto.

(also note that a colon, not a semicolon, is appropriate after "situations" to introduce a list.)

[jkeenan]

I have added p.r. GH #23437 to correct perlfunc. Suggested changes to perlsyn should be further discussed in this ticket.

[lindleyw]

Motivation for the perlsyn change is that, at least for "old-school" programmers like me coming from the days of 8080 Assembly and traditional 'C' code, concepts like defer that result in out-of-order execution are still unusual and counter-intuitive enough to warrant a few extra words of explanation.

The defer construct itself is new enough that many longtime Perl mongers might not have been exposed to it, but try/catch are so useful they deserve encouragement. I would be happy with whatever words might accomplish this goal.