Edge Specification

ABI

The application binary interface is both a construct to generate a JSON ABI by the compiler as well as a subtyping construct for contract objects.

Declaration

<abi_declaration> ::=
    "abi" <ident> [":" <ident> ("&" <ident>)*] "{"
        (
            ["mut"] <function_declaration> ";"
        )*
    "}" ;

Dependencies:

• <ident>
• <function_declaration>

The <abi_declaration> is prefixed with "abi", followed by its identifier, then an optional colon and list of ampersand separated identifiers, and finally a series of zero or more function declarations optionally prefixed by "mut" and delimited by curly braces.

Semantics

The optional "mut" keyword indicates whether the function will mutate the state of the smart contract or the EVM. This allows contracts to determine whether to use the call or staticcall instruction to interface with a target conforming to the given ABI.

The optional ampersand separated list of identifiers represents other ABI identifiers to enable ABI subtyping.

todo: revisit this. do traits satisfy this instead?