itertools php

 foreach (Multi:: zip ([ ' a ' , ' b ' ], [ 1 , 2 ]) as [ $ letter , $ number ]) {
    print ( $ letter . $ number );  // a1, b2
}

 $ result = Stream:: of ([ 1 , 1 , 2 , 2 , 3 , 4 , 5 ])
    -> distinct ()                 // [1, 2, 3, 4, 5]
    -> map ( fn ( $ x ) => $ x ** 2 )      // [1, 4, 9, 16, 25]
    -> filter ( fn ( $ x ) => $ x < 10 ) // [1, 4, 9]
    -> toSum ();                   // 14

 require_once __DIR__ . ' /vendor/autoload.php ' ;

 use IterTools  Multi ;

$ prequels  = [ ' Phantom Menace ' , ' Attack of the Clones ' , ' Revenge of the Sith ' ];
$ originals = [ ' A New Hope ' , ' Empire Strikes Back ' , ' Return of the Jedi ' ];

foreach (Multi:: chain ( $ prequels , $ originals ) as $ movie ) {
    print ( $ movie );
}
// 'Phantom Menace', 'Attack of the Clones', 'Revenge of the Sith', 'A New Hope', 'Empire Strikes Back', 'Return of the Jedi'

 use IterTools  Multi ;

$ languages = [ ' PHP ' , ' Python ' , ' Java ' , ' Go ' ];
$ mascots   = [ ' elephant ' , ' snake ' , ' bean ' , ' gopher ' ];

foreach (Multi:: zip ( $ languages , $ mascots ) as [ $ language , $ mascot ]) {
    print ( " The { $ language } language mascot is an { $ mascot } . " );
}
// The PHP language mascot is an elephant.
// ...

 $ names          = [ ' Ryu ' , ' Ken ' , ' Chun Li ' , ' Guile ' ];
$ countries      = [ ' Japan ' , ' USA ' , ' China ' , ' USA ' ];
$ signatureMoves = [ ' hadouken ' , ' shoryuken ' , ' spinning bird kick ' , ' sonic boom ' ];

foreach (Multi:: zip ( $ names , $ countries , $ signatureMoves ) as [ $ name , $ country , $ signatureMove ]) {
    $ streetFighter = new StreetFighter ( $ name , $ country , $ signatureMove );
}

 use IterTools  Multi ;

$ letters = [ ' A ' , ' B ' , ' C ' ];
$ numbers = [ 1 , 2 , 3 ];

foreach (Multi:: zipEqual ( $ letters , $ numbers ) as [ $ letter , $ number ]) {
    // ['A', 1], ['B', 2], ['C', 3]
}

 use IterTools  Multi ;

$ default = ' ? ' ;
$ letters = [ ' A ' , ' B ' ];
$ numbers = [ 1 , 2 , 3 ];

foreach (Multi:: zipFilled ( $ default , $ letters , $ numbers ) as [ $ letter , $ number ]) {
    // ['A', 1], ['B', 2], ['?', 3]
}

 use IterTools  Multi ;

$ letters = [ ' A ' , ' B ' , ' C ' ];
$ numbers = [ 1 , 2 ];

foreach (Multi:: zipLongest ( $ letters , $ numbers ) as [ $ letter , $ number ]) {
    // ['A', 1], ['B', 2], ['C', null]
}

 use IterTools  Single ;

$ movies = [
    ' Phantom Menace ' , ' Attack of the Clones ' , ' Revenge of the Sith ' ,
    ' A New Hope ' , ' Empire Strikes Back ' , ' Return of the Jedi ' ,
    ' The Force Awakens ' , ' The Last Jedi ' , ' The Rise of Skywalker '
];

foreach (Single:: chunkwise ( $ movies , 3 ) as $ trilogy ) {
    $ trilogies [] = $ trilogy ;
}
// [
//     ['Phantom Menace', 'Attack of the Clones', 'Revenge of the Sith'],
//     ['A New Hope', 'Empire Strikes Back', 'Return of the Jedi'],
//     ['The Force Awakens', 'The Last Jedi', 'The Rise of Skywalker]'
// ]

 use IterTools  Single ;

$ numbers = [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 , 10 ];

foreach (Single:: chunkwiseOverlap ( $ numbers , 3 , 1 ) as $ chunk ) {
    // [1, 2, 3], [3, 4, 5], [5, 6, 7], [7, 8, 9], [9, 10]
}

 use IterTools  Single ;

$ movies = [
    ' Phantom Menace ' , ' Attack of the Clones ' , ' Revenge of the Sith ' ,
    ' A New Hope ' , ' Empire Strikes Back ' , ' Return of the Jedi ' ,
    ' The Force Awakens ' , ' The Last Jedi ' , ' The Rise of Skywalker '
];
$ goodMovies = [ 0 , 0 , 0 , 1 , 1 , 1 , 1 , 0 , 0 ];

foreach (Single:: compress ( $ movies , $ goodMovies ) as $ goodMovie ) {
    print ( $ goodMovie );
}
// 'A New Hope', 'Empire Strikes Back', 'Return of the Jedi', 'The Force Awakens'

 use IterTools  Single ;

$ starWarsEpisodes = [
    ' I '    => ' The Phantom Menace ' ,
    ' II '   => ' Attack of the Clones ' ,
    ' III '  => ' Revenge of the Sith ' ,
    ' IV '   => ' A New Hope ' ,
    ' V '    => ' The Empire Strikes Back ' ,
    ' VI '   => ' Return of the Jedi ' ,
    ' VII '  => ' The Force Awakens ' ,
    ' VIII ' => ' The Last Jedi ' ,
    ' IX '   => ' The Rise of Skywalker ' ,
];
$ originalTrilogyNumbers = [ ' IV ' , ' V ' , ' VI ' ];

foreach (Single:: compressAssociative ( $ starWarsEpisodes , $ originalTrilogyNumbers ) as $ episode => $ title ) {
    print ( " $ episode : $ title " .  PHP_EOL );
}
// IV: A New Hope
// V: The Empire Strikes Back
// VI: Return of the Jedi

 use IterTools  Single ;

$ scores    = [ 50 , 60 , 70 , 85 , 65 , 90 ];
$ predicate = fn ( $ x ) => $ x < 70 ;

foreach (Single:: dropWhile ( $ scores , $ predicate ) as $ score ) {
    print ( $ score );
}
// 70, 85, 65, 90

 use IterTools  Single ;

$ starWarsEpisodes   = [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ];
$ goodMoviePredicate = fn ( $ episode ) => $ episode > 3 && $ episode < 8 ;

foreach (Single:: filter ( $ starWarsEpisodes , $ goodMoviePredicate ) as $ goodMovie ) {
    print ( $ goodMovie );
}
// 4, 5, 6, 7

 use IterTools  Single ;

$ reportCardGrades = [ 100 , 0 , 95 , 85 , 0 , 94 , 0 ];

foreach (Single:: filterTrue ( $ reportCardGrades ) as $ goodGrade ) {
    print ( $ goodGrade );
}
// 100, 95, 85, 94