Type Alias Expression<A>

Expression: { attributes?: Attributes; type: "expression" } & (
    A extends Model.Literal
    | Model.VariableRef
        ? { arg: A; functionRef?: Model.FunctionRef }
        : { arg?: never; functionRef: Model.FunctionRef }
)

Expressions are used in declarations and as placeholders. Each must include at least an arg or a functionRef, or both.