RPC: reals as strings #247

I'm using Jan-Klaas Kollhof's JSON-RPC implementation for Python.

My app tracks amounts using the Decimal class, in order to avoid floating point representation errors.

I should be able to do:

'{"params":["15DTr7vBr9VA52cEh2k7ywPeHL9WVFadwk","3.22","comment"],"method":"sendtoaddress","id":"1305920532.77"}'

but bitcoind returns a "got string, expected real" error because "3.22" is quoted.

If I convert the value to a float, it goes like this:

'{"params":["15DTr7vBr9VA52cEh2k7ywPeHL9WVFadwk",3.219999999,"comment"],"method":"sendtoaddress","id":"1305920532.77"}'

which is a mess.

Right now, I'm hacking around this by altering the json string after building it, using the value as a string and then stripping the double quotes to change its JSON representation to a real.

Is there a reason why a string value can't be cast into a real inside bitcoind?

Not sure if you saw this in the pull request: If you want all of your json strings to look pretty, use the latest version of simplejson that fully supports Decimal JSON values; e.g.

import decimal import simplejson simplejson.dumps(decimal.Decimal('10000000.000000009'), use_decimal=True) '10000000.000000009'

I don't like the idea of automatically casting strings to numbers in the RPC interface, it just means more lines of code to fix a problem that a) isn't a problem (3.219999999 looks ugly but behaves exactly the same as 3.22) and b) can be fixed by using the latest version of simplejson.