Specify MDJsonEncodingFailedException for failure to encode JSON through

MD_STD::json_encode

exceptions/MDJsonEncodingFailedException.php

@@ -0,0 +1,19 @@
+<?PHP
+declare(strict_types = 1);
+
+/**
+ * Reports a failure to encode JSON data.
+ */
+final class MDJsonEncodingFailedException extends Exception {
+    /**
+     * Error message.
+     *
+     * @return string
+     */
+    public function errorMessage() {
+        //error message
+        $errorMsg = 'Failed to encode JSON data.';
+        return $errorMsg;
+
+    }
+}

src/MD_STD.php

@@ -242,7 +242,7 @@ final class MD_STD {
 
         $output = \json_encode($value, $options, $depth);
         if ($output === false) {
-            throw new Exception("JSON output could not be generated");
+            throw new MDJsonEncodingFailedException("JSON output could not be generated");
         }
         return $output;
 
@@ -263,7 +263,7 @@ final class MD_STD {
 
         $output = \json_encode($value, $options, $depth);
         if ($output === false) {
-            throw new Exception("JSON output could not be generated");
+            throw new MDJsonEncodingFailedException("JSON output could not be generated");
         }
         return $output;