Re^2: print to a filehandle

That syntax never made sense to me. It's correct, but it doesn't feel right. If it's %h = %{ $h }; and @a = @{ $a }, then why isn't it print *{ $_->[0] } "moo\n"? am I going it alone on that? Perhaps I simply dont' understand the context of the filehandle in a print statement.

Hrm, perldsc leads me to believe it's just another code block (rather than a deref) so the parser can figure out it's a file handle argument ... maybe?

-Paul

Comment on Re^2: print to a filehandle Select or Download Code

Replies are listed 'Best First'.
Re^3: print to a filehandle by polettix (Vicar) on Dec 21, 2006 at 14:22 UTC
AFAIK, it's a parser issue (hence the syntax error) caused by the fact that Perl supports two flavours of `print()`, one with the filehandle and the other without it (in which case it defaults to STDOUT). When perl "sees" `$_->[0]`, it assumes that the latter flavour is in force, and by the time it arrives to `"moo\n"` it's expecting to find an operator (e.g. a comma, or a concatenation dot, or whatever). On the other hand, using the block resolves this ambiguity towards the former `print()` flavour. Flavio perl -ple'$_=reverse' <<<ti.xittelop@oivalf Don't fool yourself.	[reply] [d/l] [select]
Re^3: print to a filehandle by f00li5h (Chaplain) on Dec 21, 2006 at 13:34 UTC
I may have overheard most of a conversation stating that print is actually done as an indirect function call on a bareword (with magic to allow it to work) then again, i could have made it all up... the `prin { $_->[0] } @foo` we're seeing here is a block returning a file handle for print to write to (as perldoc says), so it's not a de-reference as `{ ... }` would suggest Update*: added some actual information `@_=qw; ask f00li5h to appear and remain for a moment of pretend better than a lifetime;;s;;@_[map hex,split'',B204316D8C2A4516DE];;y/05/os/&print;`	[reply] [d/l] [select]
Re^3: print to a filehandle by Fletch (Bishop) on Dec 21, 2006 at 14:17 UTC
Think of them all as blocks returning a value (the block `{ $h }` is returning a hashref, which is then dereferenced by `%`); this particular instance just happens to be un-sigiled because you don't normally need a sigil on the filehandle slot argument anyhow.	[reply] [d/l] [select]
Re^3: print to a filehandle by Anonymous Monk on Dec 21, 2006 at 14:22 UTC
`perldoc -f print`: Note that if you're storing FILEHANDLES in an array or other expression, you will have to use a block returning its value instead: `print { $files[$i] } "stuff\n"; print { $OK ? STDOUT : STDERR } "stuff\n";` [download]	[reply] [d/l]