Added methods to count unique characters in a string.

VERSION

@@ -1 +1 @@
-0.2302.12024
+0.2307.50127

src/AString.php

@@ -1,7 +1,7 @@
 <?php
 // AString.php
 // Created: 2021-04-26
-// Updated: 2023-01-01
+// Updated: 2023-07-05
 
 namespace Index;
 
@@ -206,6 +206,10 @@ final class AString implements IString {
         return new AString(strrev($this->value));
     }
 
+    public function countUnique(): int {
+        return XString::countUnique($this->value);
+    }
+
     public function startsWith(IString|string $text): bool {
         return str_starts_with($this->value, (string)$text);
     }

src/IString.php

@@ -1,7 +1,7 @@
 <?php
 // IString.php
 // Created: 2021-06-20
-// Updated: 2022-02-27
+// Updated: 2023-07-05
 
 namespace Index;
 
@@ -179,6 +179,13 @@ interface IString extends ArrayAccess, Countable, IteratorAggregate, JsonSeriali
      */
     function reverse(): IString;
 
+    /**
+     * Counts unique characters in a string.
+     *
+     * @return int Unique character count.
+     */
+    function countUnique(): int;
+
     /**
      * Returns a copy of the standard PHP string.
      *

src/WString.php

@@ -1,7 +1,7 @@
 <?php
 // WString.php
 // Created: 2021-06-22
-// Updated: 2022-02-27
+// Updated: 2023-07-05
 
 namespace Index;
 
@@ -166,6 +166,16 @@ final class WString implements IString {
         return new WString(implode(array_reverse($chars)), $this->encoding);
     }
 
+    public function countUnique(): int {
+        $chars = [];
+
+        foreach($this as $char)
+            if(!in_array($char, $chars, true))
+                $chars[] = $char;
+
+        return count($chars);
+    }
+
     public function __toString(): string {
         return $this->value;
     }

src/XString.php

@@ -1,7 +1,7 @@
 <?php
 // XString.php
 // Created: 2022-02-03
-// Updated: 2023-01-05
+// Updated: 2023-07-05
 
 namespace Index;
 
@@ -39,6 +39,23 @@ final class XString {
         return htmlspecialchars($value, $flags, $encoding, $doubleEncoding);
     }
 
+    /**
+     * Counts unique characters in a string.
+     *
+     * @param string String to count unique characters of.
+     * @return int Unique character count.
+     */
+    public static function countUnique(string $string): int {
+        $string = str_split($string);
+        $chars = [];
+
+        foreach($string as $char)
+            if(!in_array($char, $chars, true))
+                $chars[] = $char;
+
+        return count($chars);
+    }
+
     /**
      * Check if a string is null or empty.
      *

tests/StringTest.php

@@ -1,7 +1,7 @@
 <?php
 // StringTest.php
 // Created: 2021-04-26
-// Updated: 2022-02-27
+// Updated: 2023-07-05
 
 declare(strict_types=1);
 
@@ -278,4 +278,10 @@ final class StringTest extends TestCase {
             )->equals(new WString("\x82\xA0\x82\xA6\x82\xA8\x82\xA6\x82\xA8", 'sjis'))
         );
     }
+
+    public function testCountUnique(): void {
+        $this->assertEquals(10, XString::countUnique('iaabbccddjjefghefghi'));
+        $this->assertEquals(11, (new AString('jeff has three apples'))->countUnique());
+        $this->assertEquals(5, (new WString('みさかみこと'))->countUnique());
+    }
 }

tools/update-headers.php

@@ -1,5 +1,5 @@
 <?php
-// this file sucks, screw up the header if incomplete
+// this file sucks, screws up the header if incomplete
 // successfully corrects filenames though
 // fix this if you ever feel like it, or don't