Perl Best Practices #136: Always put filehandles in braces within any print statement. It is easier to read, helps you not to write a comma, and you do not have to remember when to use braces and when not.

Excellent example of a bogus "best practice", thank you: it is always better to know when to use curlies, and when not.

I disagree as to the bogosity of this practice. There is nothing wrong with adding clarity to a statement that may otherwise be confusing or ambiguous. And there is nothing wrong with reducing the number of rules someone needs to know in order to correctly decipher a statement.

This is just such a case, because an argument given to print can start with either a filehandle or a variable. Depending on what follows, it can be very hard to tell which is intended without braces.

I do enjoy how Perl lets one push the boundaries of acceptable syntax, but that doesn't mean it's always a good idea to do so. That's just my opinion, of course.



When's the last time you used duct tape on a duct? --Larry Wall

There is nothing wrong with adding clarity to a statement that may otherwise be confusing or ambiguous. And there is nothing wrong with reducing the number of rules someone needs to know in order to correctly decipher a statement.

How does it add clarity or reduce the number or rules?

perldoc -f print starts with

print FILEHANDLE LIST
print FILEHANDLE
print LIST

print { EXPR } LIST is not on the list at all

Where is the ambiguity?

     print  $fh  map { "$_\n" } @list;
     print {$fh} map { "$_\n" } @list;
$fh->print(      map { "$_\n" } @list );
     print( $fh  map { "$_\n" } @list );
    print( {$fh} map { "$_\n" } @list );


     print  $fh  @list;
     print {$fh} @list;
$fh->print(      @list );
     print( $fh  @list );
    print( {$fh} @list );
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This is just such a case, because an argument given to print can start with either a filehandle or a variable. Depending on what follows, it can be very hard to tell which is intended without braces.

They're both called filehandles, both STDOUT and $fh, the first argument to print is always an optional filehandle followed by a LIST

STDOUT is a bareword filehandle and $fh is a lexical-scalar filehandle