user
Task

Given the name of a language on Rosetta Code, find all tasks which are not implemented in that language.

Note: Implementations should allow for fetching more data than can be returned in one request to Rosetta Code.

You'll need to use the Media Wiki API, which you can find out about locally, here, or in Media Wiki's API documentation at, API:Query
assistant
(formerly Perl 6)

**Works with**: Rakudo version 2018.04.1

```
use HTTP::UserAgent;
use URI::Escape;
use JSON::Fast;
use Sort::Naturally;

unit sub MAIN( Str :$lang = 'Raku' );

my $client = HTTP::UserAgent.new;
my $url = 'https://rosettacode.org/w';

my @total;
my @impl;

@total.append: .&get-cat for 'Programming_Tasks', 'Draft_Programming_Tasks';
@impl = get-cat $lang;

say "Unimplemented tasks in $lang:";
my @unimplemented = (@total (-) @impl).keys.sort: *.&naturally;
.say for @unimplemented;
say "{+@unimplemented} unimplemented tasks";

sub get-cat ($category) {
    flat mediawiki-query(
        $url, 'pages',
        :generator<categorymembers>,
        :gcmtitle("Category:$category"),
        :gcmlimit<350>,
        :rawcontinue(),
        :prop<title>
    ).map({ .<title> });
}

sub mediawiki-query ($site, $type, *%query) {
    my $url = "$site/api.php?" ~ uri-query-string(
        :action<query>, :format<json>, :formatversion<2>, |%query);
    my $continue = '';

    gather loop {
        my $response = $client.get("$url&$continue");
        my $data = from-json($response.content);
        take $_ for $data.<query>.{$type}.values;
        $continue = uri-query-string |($data.<query-continue>{*}».hash.hash or last);
    }
}

sub uri-query-string (*%fields) { %fields.map({ "{.key}={uri-escape .value}" }).join("&") }

```

Output:

*As of Sept. 2, 2022*

```
Unimplemented tasks in Raku:
3d turtle graphics
15 puzzle game in 3D
Addition-chain exponentiation
Audio alarm
Audio frequency generator
Audio overlap loop
Binary coded decimal
Black box
Blackjack strategy
Boids
Catmull–Clark subdivision surface
Chess player
CLI-based maze-game
Compare sorting algorithms' performance
Compiler/AST interpreter
Compiler/Preprocessor
Compiler/syntax analyzer
Create an executable for a program in an interpreted language
Cross compilation
Cycles of a permutation
Diophantine linear system solving
Dominoes
Elevator simulation
Execute Computer/Zero
Free polyominoes enumeration
Generalised floating point multiplication
Hexapawn
Honeycombs
IRC gateway
Morpion solitaire
Number triplets game
OLE automation
OpenGL pixel shader
P-Adic square roots
Play recorded sounds
Red black tree sort
Remote agent/Agent interface
Remote agent/Agent logic
Remote agent/Simulation
Simple turtle graphics
Solve a Rubik's cube
Solving coin problems
Sorting algorithms/Tree sort on a linked list
Tamagotchi emulator
Tetris
Ukkonen’s suffix tree construction
Unicode polynomial equation
Uno (card game)
Use a REST API
Waveform analysis/Top and tail
Weather routing
WebGL rotating F
52 unimplemented tasks
```