New issue 238: CONVERT() silently accepts invalid commodity
https://bitbucket.org/blais/beancount/issues/238/convert-silently-accepts-invalid-commodity
Martin Michlmayr:
I think CONVERT() should produce an error when the commodity passed has no valid pricedb entry. Currently it simply accepts it and performs no conversion.
```
beancount> select date, position, convert(position, "XX"), balance where account ~ 'Expenses'
date position convert_p balance
---------- --------- --------- ---------
2014-01-09 10.00 EUR 10.00 EUR 10.00 EUR
2014-06-10 10.00 EUR 10.00 EUR 20.00 EUR
2014-07-30 10.00 EUR 10.00 EUR 30.00 EUR
```