Perl6 is a a really cool language I've been playing with the Rakudo and Niecza implementations I've had a bit of a go at Pugs and STD/Viv as well as Yapsi Here are some examples of features the actual source code can be found bellow in an order other than that which I expound them: here is a hello world program that pauses for input at the end. #!/usr/bin/perl6 use v6; my $msg = "Howdy"; say "$msg Cowboy"; say $*IN.get; say $*IN.lines(1); This will actually pause for two lines of input and write both of them out. I did this to show the two ways I've found to get input form stdin now called $*IN. the program actually says "Howdy Cowboy" rather than "Hello World" but since when have I been traditional. and here is another example: module Fact; multi sub postfix:<!>(Int $n) is export { [*] 1..$n; } sub prefix:<√>(Num $n) is export { return sqrt($n); } sub infix:<.oO>($name, $thought) is export { say "$name thinks $thought" } sub infix:<+->($a, $b) is export { ($a - $b) .. ($a + $b) } Note the parameters are typed also note I'm defining new operators including a postfix ! for factorial, here is an example of them in use. #!/usr/bin/env perl6-git use v6; use Fact; say 0!; say 1!; say 6!; say 10!; say √ 64.Num; say √√√256.Num; "grizzly" .oO "Perl 6 is cool"; say 2.78 ~~ 10 +- 3 ?? 't' !! 'f'; # f say 7.5 ~~ 10 +- 3 ?? 't' !! 'f'; # t say 13 ~~ 10 +- 3 ?? 't' !! 'f'; # t say 13.1 ~~ 10 +- 3 ?? 't' !! 'f'; # f Note the cast to turn Ints into Nums I shouldn't have to do this but Rakudo cannot seam to work out that Ints and Rats are Nums I'm using the current Trunk version from github to get (git clone git://github.com/rakudo/rakudo.git), Niecza cannot handle the postfix ! it lets you define this, but when you use it it thinks a prefix not ! is being abused. here are some more examples: #!/usr/bin/env perl6-git use v6; for @*ARGS -> $arg { my Num $target = $arg.Num; my Num $guess = $target; while (abs( $guess**2 - $target ) > 0.000000000000000005) { $guess += ( $target - $guess**2 ) / ( 2 * $guess ); say $guess; } say '=' x 80; } This shows how you can type variables it also shows the new @*ARGS array which replaces @ARGV as ARGV is really quite cryptic sorry C guys. #!/usr/bin/env perl6-git use v6; use Shell::Command; cat(|@*ARGS); #`« for @*ARGS -> $arg { given open($arg) { for .lines -> $line { say $line; } .close; } } » Note | is the flatten operator now bitwise or is +| for numeric and ~| for string bitwise or also note +& is numeric bitwise and and ~& for string bitwise and. Also note the #`« … » multi-line comment around the alternate implementation, you can use #`( … ) or substitute any number of [ or { followed by the same number of closing brackets or braces or parenthesis or use as many French quotes as you like « and athe same number of closing French quotes » so #`(((( some stuff on multiple lines )))) is a valid comment. here are some links for further reading
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