Added a convertCharCode() function

src/ConvertCharCode.php

@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Kiboko\Component\StringExpressionLanguage;
+
+use Symfony\Component\ExpressionLanguage\ExpressionFunction;
+
+class ConvertCharCode extends ExpressionFunction
+{
+    public function __construct($name)
+    {
+        parent::__construct(
+            $name,
+            $this->compile(...)->bindTo($this),
+            $this->evaluate(...)->bindTo($this)
+        );
+    }
+
+    private function compile(string $text, string $sourceCharCode, string $destinationCharCode): string
+    {
+        return <<<"PHP"
+            iconv($sourceCharCode, $destinationCharCode, $text)
+            PHP;
+    }
+
+    private function evaluate(array $context, string $text, string $sourceCharCode, string $destinationCharCode)
+    {
+        return iconv($sourceCharCode, $destinationCharCode, $text);
+    }
+}

src/StringExpressionLanguageProvider.php

@@ -32,6 +32,7 @@ public function getFunctions(): array
             new FormatDate('formatDate'),
             new TruncateFileName('truncateFileName'),
             new Now('now'),
+            new ConvertCharCode('convertCharCode')
         ];
     }
 }