your obfuscation magic!

Anonymous Monk has asked for the wisdom of the Perl Monks concerning the following question:

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Re: your obfuscation magic! by tobyink (Canon) on Apr 24, 2012 at 16:40 UTC
Whenever you have to do a numeric calculation, make sure you multiply by the return value from your last `print`. Speaking of `print`, there's no need to ever pass any arguments to it. `{ local $_="Hello "; local $\="world\n"; print; }` [download] `!$,` looks pretty non-obvious, but unless you've been tinkering with the `$,` variable, it's equal to 1. 1 is a number that comes up quite frequently, so be sure to use `!$,` liberally. Another synonym for 1 is `!!$$`. On that note, why say `unless $foo` when you can say `if!!$$==!$foo`. In general, most of the variables in perlvar are pretty obscure. I'll add some more later... `perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'`	[reply] [d/l] [select]
Re: your obfuscation magic! by brx (Pilgrim) on Apr 24, 2012 at 17:12 UTC
Nested loops with glob or (very very dirty) regex. First: for (1..12) { for (1..12) { for (1..12) {...}}} `#!/usr/bin/perl use strict;use warnings; my $num =3; $"=',';print join "\n",glob join "_",("{@{ [1..12] }}")x$num; ___END___ 1_1_1 1_1_2 1_1_3 1_1_4 1_1_5 1_1_6 ... 12_12_7 12_12_8 12_12_9 12_12_10 12_12_11 12_12_12` [download] same thing (without $num param) than: `print join "\n", glob "{1,2,3,4}_{1,2,3,4}_{1_2_3_4}";` Second: for $i (1 .. 12) { for $j ($i+1 .. 12) { for $k ($j+1 .. 12) {...}}} `#!/usr/bin/perl use strict;no strict 'refs';use warnings;use re 'eval'; my $num =3; $"='.?';"@{ [1..12] }" =~ /@{[ ('\b(\d+)\b')x $num]}(?{{print ((j +oin "_",map {$$_}1..$num),"\n")}})(?!)/; __END__ 1_2_3 1_2_4 1_2_5 1_2_6 1_2_7 ... 8_11_12 9_10_11 9_10_12 9_11_12 10_11_12` [download] same thing (without $num param) than: `"1 2 3 4" =~ /\b(\d+)\b.?\b(\d+)\b(?{{print "$1_$2\n"}})(?!)/;` [download] Update: $" ($LIST_SEPARATOR) permits "implicit join" (for an array interpolated in a string)	[reply] [d/l] [select]
Re: your obfuscation magic! by eyepopslikeamosquito (Archbishop) on Apr 25, 2012 at 08:30 UTC
As argued in The Lighter Side of Perl Culture (Part III): Obfu constraints are the heart of obfu. Some examples from that node: Constrain yourself to a restricted character set. For example, from A++, `${~$/&~$;&$^}++` uses only punctuation chars, while `y ccccd x s vvchr oct oct ord uc ave x s vvucve le s vvuc ave x s vvchr oct oct oct ord uc bve x eval` uses only alphabetic chars. Constrain the code to the theme of the obfu shape. For example, when tuning Saturn, I changed `O^N^E}(@X,1.6)` to `S\|A\|T\|U}(@R,$N)` to better align the code to the Saturnian theme. Find an arbitrary constraint. For example, another A++ from mtve is constrained to being a palindrome: `!$A+++!q!+++A$!`	[reply] [d/l] [select]
Re^2: your obfuscation magic! by Anonymous Monk on Apr 25, 2012 at 12:39 UTC
mm these are all interesting.. a liip using something like regex would be nice.. printing "hello world\n" 10 times for example..	[reply]
Re^3: your obfuscation magic! by Anonymous Monk on Apr 25, 2012 at 18:33 UTC
still looking for magic! :D	[reply]
Re^4: your obfuscation magic! by Anonymous Monk on Apr 25, 2012 at 19:33 UTC
Re: your obfuscation magic! by temporal (Pilgrim) on Apr 24, 2012 at 18:54 UTC
I had no idea you could replace regex delimiters with... whatever! Can't wait to make my one-liners even more annoyingly obfuscated =P	[reply]
Re^2: your obfuscation magic! by tobyink (Canon) on Apr 24, 2012 at 21:00 UTC
Beware that some delimiters have special meanings. e.g. `m/$foo/i` interpolates $foo whereas `m'$foo'i` does not. Regular expressions are not the only delimiters that can be replaced with whatever. `qq()`, `q()`, `qx()` and `qw()` work similarly. For example, the following assigns a string consisting of a single space character to $foo: `my $foo = q q q;` [download] `perl -E'sub Monkey::do{say$_,for@_,do{($monkey=[caller(0)]->[3])=~s{::}{ }and$monkey}}"Monkey say"->Monkey::do'`	[reply] [d/l] [select]