I started playing around with <a href-"http://www.perlmonks.org/index.pl?node=perlfunc%3Ado&lastnode_id=395>do, and the docs say: 
Uses the value of EXPR as a filename and executes the contents of the 
+file as a Perl script. Its primary use is to include subroutines from
+ a Perl subroutine library. 

    do 'stat.pl';

is just like 


    scalar eval `cat stat.pl`;

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So, I made a file named "print" with print "just another perl hacker\n"; in it...and went to work. First I tried: 
do ("print");
print $!, "\n" if $!;

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Which worked as expected. "just another perl hacker" was the output. Then I tried: 
do print;
print $!, "\n" if $!;

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I expected that the argument to do would be 1, since print with or without arguments evaluates to 1. So I was expecting a No such file or directory error from $!. Didn't happen. "just another perl hacker" was output as if do saw print as a string. Wondering if that was the case, I assigned a value to $_ since print assumes $_ as its argument when none is given: 
$_ = 1;
do print;
print "\n";
print $!, "\n" if $!;

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Output was "just another perl hacker". So print is being evaluated as a string I think. Just for kicks I throw some parens around it, thinking it won't matter(since it usually doesn't), but not really knowing what to expect: 
$_ = 1;
do (print);
print "\n";
print $!, "\n" if $!;

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Finally, print is evaluated down to 1, and do assigns the long awaited "No such file or directory error" to $!, so the output is:
1
No such file or directory

So, why was print evaluated as a string when not in parens? I was under the impression that Perl would recognize it as a built in function and act accordingly. Instead it acted as if it were a bareword, and there was know pre-defined sub-routine called print. And why, in this case is there a difference in the behavior with/without parentheses?

Thanks in advance.

Amel - f.k.a. - kel

In reply to The Behavior of 'do' by dsb

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