Book-currency feature and cost accounting

[Geert Janssens]

On Thursday 09 October 2014 14:30:28 Alex Aycinena wrote:
> Developers,
> 
> I am planning to add a feature to gnucash, primarily, but not
> exclusively, related to currency accounting, and wanted to summarize
> what I was thinking of. I would welcome feedback.
> 
> Since version 2.4.0, GnuCash supports trading accounts as described in
> 'Tutorial on multiple currency accounting' and 'Multiple currency
> accounting in GnuCash' by P. Selinger (see
> http://wiki.gnucash.org/wiki/Trading_Accounts). I believe Mike
> Alexander added this feature.
> 
> In his tutorial, he (P. Selinger) mentions a 'reference currency
> method' as an alternative to the use of trading accounts. This is
> essentially the feature I wish to add.
> 
> Today, in file->properties->Accounts tab, you can turn "trading
> accounts" on or off. I propose to change this to a selection of three
> alternatives: use trading accounts, specify a 'book currency', or
> neither trading accounts nor book currency. If trading accounts is
> selected, it would work as implemented by Mike. If neither is
> selected, it would work as gnucash does now without trading accounts
> selected. So no one would be forced to use the new feature.
> 
What benefit does the current situation (without trading accounts) have on its own compared 
to your new proposal ? In other words should we really keep the old way or can it be modeled 
in your new proposal as well by for example assuming a default currency ?

Or a related question: how hard would it be to migrate an existing multi-currency book without 
trading accounts to your proposal ?

Geert