codesections

#| A class that implements the Positional, Associative, and Callable roles. 
#| Accordingly, this type can be bound variables with any sigil
class Seuss does Positional does Associative does Callable does Iterable {
    has @.pos handles <AT-POS EXISTS-POS DELETE-POS ASSIGN-POS BIND-POS elems>
          = Nil, '🐠', '<°))))><'; 
    has %.asc handles <AT-KEY EXISTS-KEY DELETE-KEY ASSIGN-KEY BIND-KEY> 
          = (:blue<🐟>, :red<🐡>);
    
    method of { Mu }

codesections

# Grammar::Handles
my module Grammar::Handles::Helpers {

class X::Grammar::Can'tHandle is Exception {
    has $.type is required;
    multi method CALL-ME(|c) { die self.new(|c)}
    method message { q:to/§err/.trim.indent(2);
      The `handles` grammar trait expects a Grammar, the name
      of a Grammar, a Pair with a Grammar value, or a list of
      any of those types.  But `handles` was called with:

codesections

role Subgrammar[::G :$grammar, :$actions] {
    multi method slag(G) {
        my $old-actions = self.actions;
        self.set_actions: $actions;

        my @wrapped = G.^methods(:local).map: -> &m {
            with self.^methods.first({.name eq &m.name}) {
                next if $_ === &m or .name eq 'BUILDALL';
                .wrap: method (|c) { m self, |c } }
        }

codesections

This list was generated using the Citation Indices module by Richard Hainsworth (finanalyst) and lists the 30 most-often-depended-modules in the Raku ecosystem as of 2021-11-24 (including both direct and transitive dependencies). For more info, see the ModuleCitation module; thanks, Richard!

Module Name	Recursive Citation Index	Module Description
JSON::Fast	42.37
MIME::Base64	31.45	Encoding and decoding Base64 ASCII strings
File::Directory::Tree	30.89	Port of File::Path::Tiny - create and delete directory trees
URI	28.44	A URI implementation using Raku grammars to implement RFC 3986 BNF
OpenSSL	24.11	OpenSSL bindings
File::Temp	23.35

codesections

constant gcd      = &[gcd];
constant collect  = *.bounds;
constant extrema  = &minmax;

my &find_gcd = gcd ∘ collect ∘ extrema;

codesections

Persistent Data Structures for Raku

Synopsis

Immutable, persistent data structures give a program certain superpowers that it's very hard to have in any other way: they allow the program to "time travel" (view previous application state); they allow let the program share data across threads or asynchronously save it to disk without needing locks; they enable a much more purely functional style of programming – which results in code that many software developers find much easier to reason about. Because of these benefits, many languages with strong support for functional programming (Clojure, Elm, Haskell, etc) offer

codesections

my $result = do try {
  # some code that may throw X::This
  …
  # some code that may throw X::NotSpecified (default)
  …
  # some code that may throw X::Something
  …
  # some code that may throw X::This or X::That
  …

codesections

sub postfix:<‽>($a) { $ = $a};
class A { method n { Nil };
          method fine { self }
          method non-nil { 42}
        };
say A.new.fine‽
         .non-nil;

say A.new.n‽
         .non-nil;

codesections

in←↑⊃⎕nget '10.input' 1 ⋄ p←'#'=in

can_see←{⍺≡⍵:0
          0=+/¯1↓{p[⍵[0];⍵[1]]}¨⍺ els_btwn ⍵ }

els_btwn←{ ⍺≡⍵:⍬
           n←⍺+(⍺ slope_btwn ⍵)
           (⊂n),(n ∇ ⍵) }     

slope_btwn←{{⍵÷(∨/⍵)}-⍺-⍵}                                                         

codesections

intcode←{        
  ⍺←0 0 ⋄ (i rb)←⍺ ⋄ val←⊃⍵[0] ⋄ addr←⊃⍵[1]
  get←{ ⍵<0: ⎕←'ERR: invalid negative index'
        (addr⍳⍵)<(≢addr):(addr⍳⍵)⌷val
        addr,←⍵ ⋄ val,←0 ⋄ ∇ ⍵ }
  set←{ (addr⍳⍺)<(≢addr):((addr⍳⍺)⌷val)←⍵ 
        addr,←⍺ ⋄ val,←⍵ }      
  instr←(10 10 10 10 10)⊤(get i) ⋄ opcode←(10 10)⊥¯2↑instr ⋄ p_modes←⌽3↑instr

  p←{mode←p_modes[⍵-1]