$ret = $element->C14N($exc, $com, $xpaths, $pref);
if ($ret === false) {
    throw new RuntimeException("Error canonicalizing");
}

  Line   MyClass.php
-------------------------------
  99     Strict comparison using === between string and false will always evaluate to false.
         💡 Because the type is coming from a PHPDoc, you can turn off this check by setting treatPhpDocTypesAsCertain: false in your phpstan.neon.
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