use warnings;
print Dumpper 'Hi';
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Perl gives us two warnings:

Name "main::Dumpper" used only once: possible typo at ... line 2.
print() on unopened filehandle Dumpper at ... line 2.
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Yes you're right, I didn't use 'warnings' but shouldn't it die anyway?

No. print returns true if successful, and in this case it correctly returns undef.
map{substr$_->[0],$_->[1]||0,1}[\*||{},3],[[]],[ref qr-1,-,-1],[{}],[sub{}^*ARGV,3]

Even if a pair of braces ain't exactly required, it's still better to include them, to make sure your intent is clear. If you wrote it as print Dump($myvar); you'd receive Undefined subroutine &main::Dump called at..., but written like this, the Dumper was treated as a filehandle.

Similar to this:

If a sub named Dumperrrrrrrrrr exists, then

print Dumperrrrrrrrrr $myvar;
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print( Dumperrrrrrrrrr( $myvar ) );
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But there is no sub named Dumperrrrrrrrrr, so

print Dumperrrrrrrrrr $myvar;
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print( Dumperrrrrrrrrr $myvar );  # File handle and thing to print.
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print tries to write to Dumperrrrrrrrrr, but no file handle is associated with that symbol, so it returns false.

You can use no feature qw( bareword_filehandles ); (5.34+) to detect these errors. use v5.38; (5.38+) also does the trick (plus more).

I don't think

print( Dumperrrrrrrrrr $myvar );

helps anyone to understand what's actually going on. While the situation is more complicated in case of print, the print Dumperrrrrrrrrr $myvar; is at least syntactically the Indirect Object Syntax. If the filehandle does exist, you can think of that statement as "calling the print() method of the Dumperrrrrrr object with the parameter $myvar".

Jenda
1984 was supposed to be a warning,
not a manual!

I don't think print( Dumperrrrrrrrrr $myvar ); helps anyone to understand what's actually going on.

That's why I didn't write (just) print( Dumperrrrrrrrrr $myvar );.

And no, it's not actually an indirect method call. Or any kind of method call. It's a function (i.e. a named operator) with a funky syntax.