perl -ne}{$./'' file
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Update: Jeffa pointed out that for the above to work on *nix, you need to single quote the whole thing, which in turn means switching the single quotes to double quotes like this:

perl -ne'}{die$./""' file

A variation on thelenm's theme below

On Win32:perl -pe"}{*{'['|']'}=*."

On *nix: perl -pe'}{*{"["|"]"}=*.' file

Very clever: it avoids both an explicit print or the $_ variable by generating an error instead, that happens to state the result within the message.

perl -lpe "}{${'~'^'!'}=$." file
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Note: I get a problem running this under bash, because it interprets the ! incorrectly. But stick it in a file and it will run correctly. e.g.,

#!/usr/bin/perl -lp
}{${'~'^'!'}=$.
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perl -lpe '}{${"#"^"|"}=$.' file
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-- Mike

--
just,my${.02}

Very nice, the first post of a practical general way of avoiding $_ instead of griping about it! Not bad as an obfus technique either, especially if you do it with a different pair of chars each time.

perl -lpe '++($_=(()=<>))' < file
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_________
broquaint

Can you do it without the "_" character? I think finding ways to stick something in there implicitly will be one of the essential skills of this kind of challange.

Is it necessary to redirect file to the script instead of letting <> read the argument?

I see that the ++ compensates for the fact that one line was already read via -p. Cute.

—John

Is it necessary to redirect file to the script instead of letting <> read the argument?

Yep, otherwise it'll just hang waiting on STDIN.

Here's a solution that adheres to the rules but is awful sneaky

shell> cat > obfuwc.pl
#!/usr/bin/perl -lp -s
++(${$::{$-}}=()=<>)
^D
shell> chmod +x obfuwc.pl
shell> ./obfuwc.pl --=_ < file
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So the actual code passes the /\w/ but sneaks through the rules by passing in _. I can't say I'm proud ;)
HTH

_________
broquaint

    ()=<>;$!=$=;($:,$,,$;,$")=$!=~/.(.)..(.)(.)..(.)/;
    $;++;$*++;$;++;$*++;$;++;`$:$,$;$" $. >&$*`;
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Abigail

Patch for Windows, AIX, OSF, Solaris. Hopefully this doesn't give the game away ;)


()=<>;$!++;$!+=$!;($",$,,$:)=$!=~/.(.)...(..)....(.).+/;
$;++;$*++;$;++;$*++;$;++;`$:$,$" $. >&$*`;
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blyman

The question should be:

What is the text of the error with the code 60 on a Linux platform that fits the pattern /.(e)..(c)(e)..(o)./?

---

Examine what is said, not who speaks.

The 7th Rule of perl club is -- pearl clubs are easily damaged. Use a diamond club instead.

Very cute. I like the use of the magic in $!. But what does noze do on a Linux platform?

I've no idea what noze does on a Linux platform. ;-)

Abigail

perl -lpe'}{$_=$.' file
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Oh drat ... i just realized that mine is very similar to thelenm's and his just beat mine up ...

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

Your solution has a '_' in it, so unfortunately it matches /\w/ ...

-- Mike

--
just,my${.02}

Care to share the insight as to why he used the globs?

Sure, but this is just a hunch ...

The problem with one-liners (;)) is that Unix prefers the -e argument (the code) to be quoted with double quotes, while Win32 requires that is it be quoted with single quotes. Unix allows single quotes, but most (if not all) shells will try to interpolate the dollar signs. The following code should work on Win32, but not in UNIX:

# bash and sh
[jeffa@trinity perl]$ perl -ple "}{$_=$." foo.pl
Can't modify constant item in scalar assignment ...

# csh and tcsh
[jeffa@trinity ~/perl]$ perl -ple "}{$_=$." foo.pl
Illegal variable name.

# ksh
$ perl -ple "}{$_=$." foo.pl
Bareword found where operator expected ...
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In all of these cases, single quotes instead of double quotes would alleviate these errors. But .. it's not necessarily the double quotes themselves that cause the trouble, it's the dollar signs. So ... use globs.

perl -ple "}{*_=*." foo.pl
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Now, Abigail-II never confirmed nor denied this, so i'll treat that as a successfully executed Unix command. ;)

Update:
Of course (as jmcnamara pointed out to me via /msg), Abigail-II appears to never use Windows ... kinda throws a monkey wrench in the theory, but ... globs still get around that quoting problem.

jeffa

L-LL-L--L-LL-L--L-LL-L--
-R--R-RR-R--R-RR-R--R-RR
B--B--B--B--B--B--B--B--
H---H---H---H---H---H---
(the triplet paradiddle with high-hat)

perl -pe}{$\=$.file

command-line arguments to perl (e.g. the -le) don't count

Blah. Your challenge is too easy. With that allowed, you can do anything, trivially.

    $ perl -Mstrict='}); ()=<>; print $.; ({' -le '""' /etc/passwd
    23
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Abigail