apparently NUL is mostly whitespace in Perl?
This post will be short but baffling.
In the following snippet, the ^@ sequences indicate literal NUL bytes in the
source document.
use v5.36.0;
my $i = ^@ 1;
sub foo () {
say q^@Hell0, w0rld.^@;
$i^@++;
}
foo(^@);
say ^@$i;
This program will run and print:
Hell0, w0rld.
2
The NUL bytes are all ignored… except for the two that act as the string delimiters for the q-operator. As near as I can tell without reading any of the source for the perl tokenizer (or related code), NUL is treated like whitespace. I am gobsmacked. I know all kinds of weird stuff about Perl, but this one surprised me.
It came up when I tried to run a bunch of small programs through perltidy,
and it refused to process just one file, because it was “binary”. There was a
NUL after a subroutine’s opening brace. I removed it out, but not because it
was a syntax error. Just because it was not in good taste to leave it there.