Erlang records with both type and value restrictions as well as default values -


i trying write record represents bank account:

-record(account, {  name :: atom(),                     type :: atom(),                     balance = 0 :: integer()  }).

i want restrict balance >= 0. how do this?

something balance = 0 :: 0 | pos_integer() might trick.

edit wasn't sure existed, non_neg_integer() better :

balance = 0 :: non_neg_integer()

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