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Re: Redirect Subroutine Output

by goeb (Pilgrim)
on Aug 26, 2009 at 15:54 UTC ( #791374=note: print w/ replies, xml ) Need Help??


in reply to Redirect Subroutine Output

You could write the sub the following way:
use warnings; use strict; sub print_to { print {$_[0]} $_[1]; } print_to (*STDOUT, "test stdout"); print_to (*STDERR, "test stderr");

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Re^2: Redirect Subroutine Output
by spickles (Scribe) on Aug 26, 2009 at 18:08 UTC
    goeb -

    Why do I get the error 'scalar found where operator expected' if I omit the braces around the $_[0]? What are the braces doing and why aren't they required around the second element?

    Regards,
    Scott
      From the docs for print:
      Note that if you're storing FILEHANDLEs in an array, or if you're using any other expression more complex than a scalar variable to retrieve it, you will have to use a block returning the filehandle value instead:
      I believe the braces define a block of code, and I believe $_[0] qualifies as an 'expression more complex than a scalar variable'. If you refactor the sub like this, then the braces around the FILEHANDLE are not needed:
      use warnings; use strict; sub print_to { my ($fh, $str) = @_; print $fh $str; } print_to (*STDOUT, "test stdout"); print_to (*STDERR, "test stderr");

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