coyle

+ satisfied implicitly 
    + don't need to decalre, having the necessary methods is enough

1. interfaces as contracts
    - Abstract type
    - doesn't expose the representation or internal structure of it's values or the set of basic operations the support
    - Only reveals a subset of methods
    - Know nothing about what it is only what it can do (what behaviors are provided by their methods)
    - Fprintf / substitutability 
        - https://golang.org/pkg/fmt/#Fprintf

coyle

Keybase proof

I hereby claim:

• I am coyle on github.
• I am dcoyle (https://keybase.io/dcoyle) on keybase.
• I have a public key ASCSFu4jVTt0mdViCm_LMC8VoYwQ90vE9ioHm3fs0k2sVQo

To claim this, I am signing this object:

coyle

[ 'US',
  'AW',
  'AF',
  'AO',
  'AI',
  'AX',
  'AL',
  'AD',
  'AE',
  'AR',