m_exchange_rates
Read currency rates and convert amounts using the site's mod_exchange_rates
server. Rates express currency units per USD and may be retained from earlier
updates. No ACL check is applied by this model.
| Template path | Result |
|---|---|
m.exchange_rates.base_currency | Base currency code, USD. |
m.exchange_rates.currencies | Sorted list of known binary currency codes. |
m.exchange_rates.rates | Map from binary currency codes to rates. |
m.exchange_rates.convert[from][to][amount] | Converted numeric amount. |
For example:
{{ m.exchange_rates.convert["USD"]["EUR"][100] }}
The conversion path order is source currency, destination currency, amount.
Its Erlang equivalent is
mod_exchange_rates:convert(100, <<"USD">>, <<"EUR">>, Context).
Conversion follows the rounding rules documented by mod_exchange_rates;
missing or unavailable currencies return currency_from or currency_to
errors. The m_get/3 callback wraps successful values as
{ok, {Value, Rest}} and propagates conversion errors. There is no catch-all
clause for unsupported model paths.