b2gills

  ( 2..∞ ).grep( *.is-prime )

  2, 4, 8 ... *

  2, 4, 8, * × 2 ... *

  2, 4, 9 ... *

  Unable to deduce arithmetic or geometric sequence from: 2, 4, 9
  Did you really mean '..'?
  in block at ./example.raku line 1

  say [+] 1..10000000000000000000000000000000000000000000

  role Singleton {
    method new (|) {
      once callsame
    }
  }

  class Foo does Singleton {
    has $.n is required
  }

  say Foo.new( n => 1 ).n;
  say Foo.new( n => 2 ).n;

  my $string = 'AAABBBCCC';

  say $string ~~ /
    ^

    # match at least one A
    # store the result in a named sub-entry
    $<A> = [ A+ ]

    {} # update result object

    # create a lexical var named $repetition
    :my $repetition = $<A>.chars(); # <- embedded Raku syntax

    # match B and then C exactly $repetition times
    $<B> = [ B ** {$repetition} ]
    $<C> = [ C ** {$repetition} ]
  
    $
  /;

  ｢AAABBBCCC｣
  A => ｢AAA｣
  B => ｢BBB｣
  C => ｢CCC｣

    0 but True

    my $role = role { method Bool { True }}

    0 but role { method Bool { True }}

    0 but True

    do {
      my constant but-true = anon role { method Bool { True }}
      my $class = anon class :: is Int does but-true {}

      $class.new( 0 )
    }

  my &infix:< · > = &infix:< × >;

  sub infix:< · > (+@vals)
    is equiv(&[×])       # uses the same precedence level etc.
    is assoc<chaining>   # may not be necessary given previous line
  {
    [×] @vals            # reduction using infix operator
  }

  # I don't know what precedence level it is supposed to be
  proto infix:< ∧ > (|) is tighter(&[×]) {*}

  multi infix:< ∧ > (
    Numeric $l,
    Numeric $r,
  ) {
    $l × $r
  }

  multi infix:< ∧ > (
    Vector $l, # need to define this somewhere, or use List/Array
    Vector $r,
  ) {
    …
  }

  [[1,2,3],[4,5,6]] »×« [[10,20,30],[40,50,60]]
  # [[10,40,90],[160,250,360]]

  # generate a synthetic `»×«` operator, and give it an alias
  my &infix:< ∧ > = &infix:< »×« >;

  [[1,2,3],[4,5,6]] ∧ [[10,20,30],[40,50,60]]
  # [[10,40,90],[160,250,360]]

    say π ≤ 3+⅘ ≤ τ
    # True

    say π² ÷ 4
    # 2.4674011002723395

    # this assumes that ϕ, ψ, and θ have already been set

    my \cϕ = ϕ.cos; my \sϕ = ϕ.sin;
    my \cψ = ψ.cos; my \sψ = ψ.sin;
    my \cθ = θ.cos; my \sθ = θ.sin;

    my \alpha = [ cψ×cϕ−cθ×sϕ×sψ,   cψ×sϕ+cθ×cϕ×sψ,   sψ×sθ;
               −sψ×cϕ−cθ×sϕ×cψ,  −sψ×sϕ+cθ×cϕ×cψ,   cψ×sθ;
                sθ×sϕ,           −sθ×cϕ,            cθ];

    say "ϕψθ".uniprops;
    # (Ll Ll Ll)