Raku language preview

1. A class with accessors

twigils, the is rw trait, and a declarator doc

horizon-dark

#| doubles a number
sub double(Int $x) {
    return $x * 2;
}

my $name = "world";
say "Hello, $name!";

class Point {
    has $.x is rw;
    has $.y is rw;
}

my $p = Point.new(x => 1, y => 2);
say $p.x ~~ $p.y;

atom-one-dark

#| doubles a number
sub double(Int $x) {
    return $x * 2;
}

my $name = "world";
say "Hello, $name!";

class Point {
    has $.x is rw;
    has $.y is rw;
}

my $p = Point.new(x => 1, y => 2);
say $p.x ~~ $p.y;

github-dark

#| doubles a number
sub double(Int $x) {
    return $x * 2;
}

my $name = "world";
say "Hello, $name!";

class Point {
    has $.x is rw;
    has $.y is rw;
}

my $p = Point.new(x => 1, y => 2);
say $p.x ~~ $p.y;

dracula

#| doubles a number
sub double(Int $x) {
    return $x * 2;
}

my $name = "world";
say "Hello, $name!";

class Point {
    has $.x is rw;
    has $.y is rw;
}

my $p = Point.new(x => 1, y => 2);
say $p.x ~~ $p.y;

nord

#| doubles a number
sub double(Int $x) {
    return $x * 2;
}

my $name = "world";
say "Hello, $name!";

class Point {
    has $.x is rw;
    has $.y is rw;
}

my $p = Point.new(x => 1, y => 2);
say $p.x ~~ $p.y;

github

#| doubles a number
sub double(Int $x) {
    return $x * 2;
}

my $name = "world";
say "Hello, $name!";

class Point {
    has $.x is rw;
    has $.y is rw;
}

my $p = Point.new(x => 1, y => 2);
say $p.x ~~ $p.y;

2. Grammar and tokens

the grammar, token, and rule keywords

horizon-dark

grammar Calculator {
    token TOP { <expr> }
    rule expr { <num> '+' <num> }
    token num { \d+ }
}

atom-one-dark

grammar Calculator {
    token TOP { <expr> }
    rule expr { <num> '+' <num> }
    token num { \d+ }
}

github-dark

grammar Calculator {
    token TOP { <expr> }
    rule expr { <num> '+' <num> }
    token num { \d+ }
}

dracula

grammar Calculator {
    token TOP { <expr> }
    rule expr { <num> '+' <num> }
    token num { \d+ }
}

nord

grammar Calculator {
    token TOP { <expr> }
    rule expr { <num> '+' <num> }
    token num { \d+ }
}

github

grammar Calculator {
    token TOP { <expr> }
    rule expr { <num> '+' <num> }
    token num { \d+ }
}

3. Multi dispatch

multi and proto subs

horizon-dark

proto sub area(|) {*}
multi sub area(Num $r) { pi * $r ** 2 }
multi sub area(Num $w, Num $h) { $w * $h }

atom-one-dark

proto sub area(|) {*}
multi sub area(Num $r) { pi * $r ** 2 }
multi sub area(Num $w, Num $h) { $w * $h }

github-dark

proto sub area(|) {*}
multi sub area(Num $r) { pi * $r ** 2 }
multi sub area(Num $w, Num $h) { $w * $h }

dracula

proto sub area(|) {*}
multi sub area(Num $r) { pi * $r ** 2 }
multi sub area(Num $w, Num $h) { $w * $h }

nord

proto sub area(|) {*}
multi sub area(Num $r) { pi * $r ** 2 }
multi sub area(Num $w, Num $h) { $w * $h }

github

proto sub area(|) {*}
multi sub area(Num $r) { pi * $r ** 2 }
multi sub area(Num $w, Num $h) { $w * $h }