6lang/Perl 6 Golfing Cheatsheet

As I'm getting bored with code golf, I decided to share some of the tricks with the world. If that document makes golfing less fun for you, you can close your eyes while reading it.

Please note: This document is mostly focused on golf platforms that count codepoints instead of UTF-8 bytes. That said, I will try to include unicode-unrelated tricks too.

Also: This document does not list everything and probably it never will. Contributions are welcome.

Numbers

Unicode

If one of the numbers that you are using is one of these:

NaN -0.5 0.00625 0.025 0.0375 0.05 0.0625 0.083333 0.1 0.111111 0.125
0.142857 0.15 0.166667 0.1875 0.2 0.25 0.333333 0.375 0.4 0.416667 0.5
0.583333 0.6 0.625 0.666667 0.75 0.8 0.833333 0.875 0.916667 1 1.5 2
2.5 3 3.5 4 4.5 5 5.5 6 6.5 7 7.5 8 8.5 9 10 11 12 13 14 15 16 17 18
19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41
42 43 44 45 46 47 48 49 50 60 70 80 90 100 200 300 400 500 600 700 800
900 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000 20000 30000
40000 50000 60000 70000 80000 90000 100000 200000 216000 300000 400000
432000 500000 600000 700000 800000 900000 1000000 100000000
10000000000 1000000000000

# perl6 -e 'for ^0x10FFFF { .unival.say }' | sort -un

Then use the corresponding unicode character.

say ㊿
#   50

say 兆
#   1000000000000

Whitespace between numbers and ops

say 2 xx 3

say ②xx③

Topic variable increment

say $_++

say .++

Strings

Use uninames, error messages and other built-in strings instead of string literals:

say (‘♔’…‘♙’)».uniname».words»[2]
#   KING QUEEN ROOK BISHOP KNIGHT PAWN

Lists

my ($a, $b, $c) = 42, 52, 62;
my$z=«25$a$b$c»
#    (25,$a,$b,$c)

Loops

This one is a bit tough to get into your code, but it does help sometimes:

 say(42)for ^10
#say(42)xx⑤

Conditionals

Use junctions if possible

say 42 if 0||1

say 42 if 0|1

Note that you can use junctions as sub args, and you get a junction back.

1-character if-then

42==42&&say ‘hello’;
42==42>say ‘hello’;
42==42≠say ‘hello’;

Other

Base 0x10FFFF

This techique is explained in more detail in this post.

infix .

say (^50).max;
say ^50 .max;

labster/6lang-golf-cheatsheet