Re: Adding a try/catch syntax to Perl

If we had an LR parser in play that did not require an early commitment to
the rule to be expanded, instead of an LL one that does, we could offer the
more expressive:

  {...}  fail  {...}

where *fail* is a dyadic operator linking the *try* part to the *catch*
part.

But of course that would be advanced language technology that transcended
Java or Javascript when our goal, these days, is, apparently, to be as much
like them as possible, yea verily, right down to the very last parenthesis:

We are not now that strength which in old days
Moved earth and heaven;


On Fri, Jan 22, 2021 at 7:09 PM Paul "LeoNerd" Evans <leonerd@leonerd.org.uk>
wrote:

> On Fri, 22 Jan 2021 13:47:52 -0500
> Dan Book <grinnz@gmail.com> wrote:
>
> > The parentheses also enable future extensions with arbitrary syntax
> > such as typed dispatch.
>
> ^-- yes, that.
>
> I have been thinking several steps ahead here. While not a part of my
> *current* proposal for core, I do aim that one day we can
>
>   try { ... }
>   catch ($e isa MyApp::SomeWeirdException) { ... }
>   catch ($e isa Perl::X::ENOENT) { ... }
>   catch ($e) { default here }
>
> So the parens are necessary for those later forward steps.
>
> If you want to see the full and varied discussions about the history of
> that part of Syntax::Keyword::Try, see [while rt.cpan.org is still a
> thing]:
>
>   https://rt.cpan.org/Ticket/Display.html?id=123918
>
> --
> Paul "LeoNerd" Evans
>
> leonerd@leonerd.org.uk      |  https://metacpan.org/author/PEVANS
> http://www.leonerd.org.uk/  |  https://www.tindie.com/stores/leonerd/
>


-- 
Thanks,

Phil <https://metacpan.org/author/PRBRENAN>

Philip R Brenan <https://metacpan.org/author/PRBRENAN>

• Adding a try/catch syntax to Perl by Paul "LeoNerd" Evans
• Re: Adding a try/catch syntax to Perl by =?UTF-8?Q?Branislav_Zahradn=C3=ADk?=
• Re: Adding a try/catch syntax to Perl by Paul "LeoNerd" Evans
• Re: Adding a try/catch syntax to Perl by Chad Granum
• Re: Adding a try/catch syntax to Perl by Philip R Brenan
• Re: Adding a try/catch syntax to Perl by Felipe Gasper
• Re: Adding a try/catch syntax to Perl by Dan Book
• Re: Adding a try/catch syntax to Perl by Paul "LeoNerd" Evans
• Re: Adding a try/catch syntax to Perl by Philip R Brenan
• Re: Adding a try/catch syntax to Perl by Paul "LeoNerd" Evans
• Re: Adding a try/catch syntax to Perl by Philip R Brenan
• Re: Adding a try/catch syntax to Perl by Paul "LeoNerd" Evans
• Re: Adding a try/catch syntax to Perl by Philip R Brenan
• Re: Adding a try/catch syntax to Perl by Andy Broad
• Re: Adding a try/catch syntax to Perl by Paul "LeoNerd" Evans
• Re: Adding a try/catch syntax to Perl by Paul "LeoNerd" Evans