Canvas

     (class->interface editor-canvas%)
                   |
            canvas:basic<%>
                   |
        +----------+----------+
        |                     |
  canvas:info<%>      canvas:wide-snip<%>

• canvas:basic<%>
• canvas:basic-mixin
• canvas:info<%>
• canvas:info-mixin
• canvas:wide-snip<%>
• canvas:wide-snip-mixin
• canvas:basic% = (canvas:basic-mixin editor-canvas%)
• canvas:info% = (canvas:info-mixin canvas:basic%)
• canvas:wide-snip% = (canvas:wide-snip-mixin canvas:basic%)