Re: use Fatal;

[George_Sherston]

in reply to use Fatal;

This sounds like a Good Thing (tm) - cuts down on typing / file size (marginally, but it all helps) and more importantly makes sure I don't forget to do the error checking.

Looking at the docs, it looks admirably flexible:

C<Fatal> provides a way to conveniently replace functions which normally return a false value when they fail with equivalents which halt execution if they are not successful.

As I read it, this means if I have a function 'foo' that sometimes returns false, and I'd like to know about that for test purposes, say, I can do import Fatal 'foo'; Thus where I have

use Fatal;
import Fatal 'foo';

sub foo {
my $test = rand;
return $test if $test > .5;
}

my $test = foo();
print $test;

Each time rand is less than .5, I get

Can't foo(), $! is "No such file or directory" at (eval 1) line 3
        main::__ANON__() called at p.pl line 10

... which is better than nothing.

The only reason I can think of for doing my own error checking is so that I can supply my own useful info about the failure. So for example I probably wouldn't use this for error-checking DBI function calls, because I would want to add $dbh->errstr.

Thanks for drawing attention to this.

§ George Sherston

[cLive ;-)]

Actually, DBI is where I was thinking of bringing it in, combined with a custom $SIG{__DIE__}, eg:

local $SIG{__die__} = sub {
    die ("DBI Error: $DBI::errstr") if $DBI::errstr;
    die $!;
};

But make sure you explicitly refer to the error (ie, don't use OO method unless method will definitely be in scope in the sub).

Could be very useful...

cLive ;-)

[perrin]

No need to use fatal with DBI. Just set DBI's RaiseError flag to true. You can even use eval() to catch exceptions with it.