message: Throw proper exception when string -> numeric conversion fails
diff: @@ -123,19 +123,35 @@ template <> int16_t Cast::Operation(const char *left) {
  }
  template <> int Cast::Operation(const char *left) {
  + try {
  return stoi(left, NULL, 10);
  + } catch(...) {
  + throw ConversionException("Could not convert string '%s' to numeric", left);
  + }
  }
  template <> int64_t Cast::Operation(const char *left) {
  + try {
  return stoll(left, NULL, 10);
  + } catch(...) {
  + throw ConversionException("Could not convert string '%s' to numeric", left);
  + }
  }
  template <> uint64_t Cast::Operation(const char *left) {
  + try {
  return stoull(left, NULL, 10);
  + } catch(...) {
  + throw ConversionException("Could not convert string '%s' to numeric", left);
  + }
  }
  template <> double Cast::Operation(const char *left) {
  + try {
  return stod(left, NULL);
  + } catch(...) {
  + throw ConversionException("Could not convert string '%s' to numeric", left);
  + }
  }
  //===--------------------------------------------------------------------===//
  