code: function checkSentHeader(validator, def, name, value) {
    if(!value && def.default) {
      return def.def.default;
    }
    var err = validator(value, def.schema);
    if(err) {
      debug("Implementation Spec Violation: Unmatching sent header format: " +
        name);
      debug(err);
      throw new ValidationError("Unmatching response format", 500);
    }
  }
docs: Checks a sent header and logs the exact violation in swagger:check
  @param validator {function(object, Schema)} JSON-Schema validator function
  @param def {Header} The header definition
  @param name {string} The header's name
  @param value {*} The header value
  @throws {ValidationError} When the header does not respect the schema