hincludes/lib/Lambda.class.php

   1 <?php
   2
   3 class Lambda {
   4         public function __construct(){}
   5         static function harray($it) {
   6                 $a = new _hx_array(array());
   7                 if(null == $it) throw new HException('null iterable');
   8                 $»it = $it->iterator();
   9                 while($»it->hasNext()) {
  10                         $i = $»it->next();
  11                         $a->push($i);
  12                 }
  13                 return $a;
  14         }
  15         static function hlist($it) {
  16                 $l = new HList();
  17                 if(null == $it) throw new HException('null iterable');
  18                 $»it = $it->iterator();
  19                 while($»it->hasNext()) {
  20                         $i = $»it->next();
  21                         $l->add($i);
  22                 }
  23                 return $l;
  24         }
  25         static function map($it, $f) {
  26                 $l = new HList();
  27                 if(null == $it) throw new HException('null iterable');
  28                 $»it = $it->iterator();
  29                 while($»it->hasNext()) {
  30                         $x = $»it->next();
  31                         $l->add(call_user_func_array($f, array($x)));
  32                 }
  33                 return $l;
  34         }
  35         static function mapi($it, $f) {
  36                 $l = new HList();
  37                 $i = 0;
  38                 if(null == $it) throw new HException('null iterable');
  39                 $»it = $it->iterator();
  40                 while($»it->hasNext()) {
  41                         $x = $»it->next();
  42                         $l->add(call_user_func_array($f, array($i++, $x)));
  43                 }
  44                 return $l;
  45         }
  46         static function has($it, $elt, $cmp = null) {
  47                 if($cmp === null) {
  48                         if(null == $it) throw new HException('null iterable');
  49                         $»it = $it->iterator();
  50                         while($»it->hasNext()) {
  51                                 $x = $»it->next();
  52                                 if($x == $elt) {
  53                                         return true;
  54                                 }
  55                         }
  56                 } else {
  57                         if(null == $it) throw new HException('null iterable');
  58                         $»it = $it->iterator();
  59                         while($»it->hasNext()) {
  60                                 $x = $»it->next();
  61                                 if(call_user_func_array($cmp, array($x, $elt))) {
  62                                         return true;
  63                                 }
  64                         }
  65                 }
  66                 return false;
  67         }
  68         static function exists($it, $f) {
  69                 if(null == $it) throw new HException('null iterable');
  70                 $»it = $it->iterator();
  71                 while($»it->hasNext()) {
  72                         $x = $»it->next();
  73                         if(call_user_func_array($f, array($x))) {
  74                                 return true;
  75                         }
  76                 }
  77                 return false;
  78         }
  79         static function hforeach($it, $f) {
  80                 if(null == $it) throw new HException('null iterable');
  81                 $»it = $it->iterator();
  82                 while($»it->hasNext()) {
  83                         $x = $»it->next();
  84                         if(!call_user_func_array($f, array($x))) {
  85                                 return false;
  86                         }
  87                 }
  88                 return true;
  89         }
  90         static function iter($it, $f) {
  91                 if(null == $it) throw new HException('null iterable');
  92                 $»it = $it->iterator();
  93                 while($»it->hasNext()) {
  94                         $x = $»it->next();
  95                         call_user_func_array($f, array($x));
  96                 }
  97         }
  98         static function filter($it, $f) {
  99                 $l = new HList();
 100                 if(null == $it) throw new HException('null iterable');
 101                 $»it = $it->iterator();
 102                 while($»it->hasNext()) {
 103                         $x = $»it->next();
 104                         if(call_user_func_array($f, array($x))) {
 105                                 $l->add($x);
 106                         }
 107                 }
 108                 return $l;
 109         }
 110         static function fold($it, $f, $first) {
 111                 if(null == $it) throw new HException('null iterable');
 112                 $»it = $it->iterator();
 113                 while($»it->hasNext()) {
 114                         $x = $»it->next();
 115                         $first = call_user_func_array($f, array($x, $first));
 116                 }
 117                 return $first;
 118         }
 119         static function count($it, $pred = null) {
 120                 $n = 0;
 121                 if($pred === null) {
 122                         if(null == $it) throw new HException('null iterable');
 123                         $»it = $it->iterator();
 124                         while($»it->hasNext()) {
 125                                 $_ = $»it->next();
 126                                 $n++;
 127                         }
 128                 } else {
 129                         if(null == $it) throw new HException('null iterable');
 130                         $»it = $it->iterator();
 131                         while($»it->hasNext()) {
 132                                 $x = $»it->next();
 133                                 if(call_user_func_array($pred, array($x))) {
 134                                         $n++;
 135                                 }
 136                         }
 137                 }
 138                 return $n;
 139         }
 140         static function hempty($it) {
 141                 return !$it->iterator()->hasNext();
 142         }
 143         static function indexOf($it, $v) {
 144                 $i = 0;
 145                 if(null == $it) throw new HException('null iterable');
 146                 $»it = $it->iterator();
 147                 while($»it->hasNext()) {
 148                         $v2 = $»it->next();
 149                         if($v == $v2) {
 150                                 return $i;
 151                         }
 152                         $i++;
 153                 }
 154                 return -1;
 155         }
 156         static function concat($a, $b) {
 157                 $l = new HList();
 158                 if(null == $a) throw new HException('null iterable');
 159                 $»it = $a->iterator();
 160                 while($»it->hasNext()) {
 161                         $x = $»it->next();
 162                         $l->add($x);
 163                 }
 164                 if(null == $b) throw new HException('null iterable');
 165                 $»it = $b->iterator();
 166                 while($»it->hasNext()) {
 167                         $x = $»it->next();
 168                         $l->add($x);
 169                 }
 170                 return $l;
 171         }
 172         function __toString() { return 'Lambda'; }
 173 }