Add :unknown implementation to impl-case

Description

Problem

Sometimes we want a default case when no implementation is specified in
impl-case. Since it throws an exception when falling through, we need
an explicit :unknown implementation.

Solution

Add :unknown implementation by default.

Pull request: 44
Patch: ctyp-256.patch
Commit: 856abf
Release: 0.3.9

Environment

None

Assignee

Ambrose Bonnaire-Sergeant

Reporter

Ambrose Bonnaire-Sergeant

Labels

None

Approval

None

Patch

None

Components

Fix versions

Priority

Trivial
Configure