phpman > man > Fatal(3pm)

NAME
    Fatal - Replace functions with equivalents which succeed or die

SYNOPSIS
        use Fatal qw(open close);

        open(my $fh, "<", $filename);  # No need to check errors!

        use File::Copy qw(move);
        use Fatal qw(move);

        move($file1, $file2); # No need to check errors!

        sub juggle { . . . }
        Fatal->import('juggle');

BEST PRACTICE
    Fatal has been obsoleted by the new autodie pragma. Please use autodie in preference to "Fatal".
    autodie supports lexical scoping, throws real exception objects, and provides much nicer error
    messages.

    The use of ":void" with Fatal is discouraged.

DESCRIPTION
    "Fatal" provides a way to conveniently replace functions which normally return a false value
    when they fail with equivalents which raise exceptions if they are not successful. This lets you
    use these functions without having to test their return values explicitly on each call.
    Exceptions can be caught using "eval{}". See perlfunc and perlvar for details.

    The do-or-die equivalents are set up simply by calling Fatal's "import" routine, passing it the
    names of the functions to be replaced. You may wrap both user-defined functions and overridable
    CORE operators (except "exec", "system", "print", or any other built-in that cannot be expressed
    via prototypes) in this way.

    If the symbol ":void" appears in the import list, then functions named later in that import list
    raise an exception only when these are called in void context--that is, when their return values
    are ignored. For example

        use Fatal qw/:void open close/;

        # properly checked, so no exception raised on error
        if (not open(my $fh, '<', '/bogotic') {
            warn "Can't open /bogotic: $!";
        }

        # not checked, so error raises an exception
        close FH;

    The use of ":void" is discouraged, as it can result in exceptions not being thrown if you
    *accidentally* call a method without void context. Use autodie instead if you need to be able to
    disable autodying/Fatal behaviour for a small block of code.

DIAGNOSTICS
    Bad subroutine name for Fatal: %s
        You've called "Fatal" with an argument that doesn't look like a subroutine name, nor a
        switch that this version of Fatal understands.

    %s is not a Perl subroutine
        You've asked "Fatal" to try and replace a subroutine which does not exist, or has not yet
        been defined.

    %s is neither a builtin, nor a Perl subroutine
        You've asked "Fatal" to replace a subroutine, but it's not a Perl built-in, and "Fatal"
        couldn't find it as a regular subroutine. It either doesn't exist or has not yet been
        defined.

    Cannot make the non-overridable %s fatal
        You've tried to use "Fatal" on a Perl built-in that can't be overridden, such as "print" or
        "system", which means that "Fatal" can't help you, although some other modules might. See
        the "SEE ALSO" section of this documentation.

    Internal error: %s
        You've found a bug in "Fatal". Please report it using the "perlbug" command.

BUGS
    "Fatal" clobbers the context in which a function is called and always makes it a scalar context,
    except when the ":void" tag is used. This problem does not exist in autodie.

    "Used only once" warnings can be generated when "autodie" or "Fatal" is used with package
    filehandles (eg, "FILE"). It's strongly recommended you use scalar filehandles instead.

AUTHOR
    Original module by Lionel Cons (CERN).

    Prototype updates by Ilya Zakharevich <ilya AT math.edu>.

    autodie support, bugfixes, extended diagnostics, "system" support, and major overhauling by Paul
    Fenwick <pjf AT perltraining.au>

LICENSE
    This module is free software, you may distribute it under the same terms as Perl itself.

SEE ALSO
    autodie for a nicer way to use lexical Fatal.

    IPC::System::Simple for a similar idea for calls to "system()" and backticks.