VIP: Make the type argument in method_id optional

[iamdefinitelyahuman]

Simple Summary

method_id's second argument (the output type) should be optional with a default of bytes[4].

Motivation

• Generating a 4 byte function selector is by far the most common use-case for this method
• The 32 byte flavor is just as easily achieved using keccak256

Specification

method_id(method, output_type=bytes[4]) → Union[bytes[4], bytes32]

output_type may still be given as a positional arg so that this is not a breaking change.

Backwards Compatibility

No issues.

Copyright

Copyright and related rights waived via CC0

[fubuloubu]

I was thinking to remove output_type entirely, and figure out bytes[4] or bytes32 based on context (calls or events)

[iamdefinitelyahuman]

That sounds pretty magical.

[fubuloubu]

Not really, it should be obvious because it is only useful as bytes[4] for calls, and only useful as bytes32 for events. I don't think the user needs to know this detail.