clear shelf-type? shelf-name

Use clear to remove all items from the given shelf.

This function is not allowed on shelves with a fixed size, and it cannot be cleared if it is currently the subject of a repeat over.

The shelf-type is an optional herald.

If a number of clear actions occur consecutively, the keyword clear can be replaced in the second and subsequent actions by the keyword and or the "&" operator. This form is deprecated as it does not increase readability.