You can also use diagnostics to get more helpful info:

Unquoted string "erase" may clash with future reserved word at  (#1)
    (W reserved) You used a bareword that might someday be claimed as 
+a
    reserved word.  It's best to put such a word in quotes, or capital
+ize it
    somehow, or insert an underbar into it.  You might also declare it
+ as a
    subroutine.
[download]

It tells you that you can capitalize it; ERASE will avoid the warning messages. Underscores work too. Quoting could also work, but you'd have to use curly braces in your print:

print {"erase"} "LOL";
[download]

However, a more modern coding style uses lexical filehandles, the 3-arg form of open and autodie to check success:

use warnings;
use strict;
use autodie;

open my $fh, '>', 'lol.txt';
print $fh 'LOL';
close $fh;
[download]