Re: Lexical filehandles: unblessed but (sometimes) can

$fh contains a reference to a glob. The glob isn't blessed. However, the IO object referenced by the glob is blessed.

$ perl -MScalar::Util=blessed,reftype -E'
   open my $fh, ">", \my $buf;
   say reftype($fh) // "[not a ref]";
   say blessed($fh) // "[not blessed]";
   say reftype(*$fh{IO}) // "[not a ref]";
   say blessed(*$fh{IO}) // "[not blessed]";
'
GLOB
[not blessed]
IO
IO::File
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Comment on Re: Lexical filehandles: unblessed but (sometimes) can Select or Download Code

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Re^2: Lexical filehandles: unblessed but (sometimes) can by vr (Curate) on Mar 15, 2018 at 21:02 UTC
`use strict; use warnings; use feature qw/ say /; use Scalar::Util qw/ blessed/; open my $fh, ">", undef; say blessed( $fh{ IO }); # IO::File say $fh{ IO }-> can( "print" ) ? "yes" : "no"; # no autoflush $fh 1; say $fh{ IO }-> can( "print" ) ? "yes" : "no"; # yes` [download] And: `use strict; use warnings; use Log::Log4perl qw / :easy /; use Log::Dispatch::Handle; open my $fh, ">", undef; #autoflush $fh 1; my $app = Log::Log4perl::Appender-> new( "Log::Dispatch::Handle", handle => $fh{ IO }); __END__ The IO::File class is missing the 'print' method` [download] And uncommenting the comment makes the program run OK and error message gone.	[reply] [d/l] [select]
Re^3: Lexical filehandles: unblessed but (sometimes) can by ikegami (Patriarch) on Mar 16, 2018 at 20:18 UTC
That's because IO::File is loaded on demand. (One used to have to load it explicitly.) You can change the output to yes-yes by explicitly loading it.	[reply]
Re^4: Lexical filehandles: unblessed but (sometimes) can by vr (Curate) on Mar 17, 2018 at 13:45 UTC
Simple answer to seemingly complex problem. Thank you.	[reply]