Do we need the notion of interfaces or ports on contracts?

[markusvoelter]

For example, if a contract "contains" an ERC20 token, can its operations be made available through a dedicated port?

[markusvoelter]

There is a whole group of issues relating to the collaboration between contracts:

• https://github.com/ethereum/langlab/issues/2
• https://github.com/ethereum/langlab/issues/4
• https://github.com/ethereum/langlab/issues/14
• https://github.com/ethereum/langlab/issues/15