Incorrect context for indexing into a shelf.

#2058 Compile-time error

Incorrect context for indexing into a shelf.

Additional Information

X selection is not allowed with the 'Y' action.
    where X is item or key, and Y is clear, new, REPEAT OVER, save or save-clear.
    or
X selection is not allowed with the 'Y' condition.
    where X is item or key, and Y is 'has key.'
    or
X selection is not allowed in conjunction with 'NUMBER-OF'.
    where X is item or key.
    or
The IS SPECIFIED attribute test cannot be combined with an ITEM selection.
    or
The 'X' stream cannot be indexed with 'Y' selection.
    where X is output, #output, or markup and Y is item or key.
    or
The 'X' is a scalar shelf, and cannot be indexed.
    where X is the name of a counter, stream, or switch.

Recovery

Compilation continues but no compiled source code file will be saved.

Explanation

The item phrase may be used only where it makes sense to work with one particular value of the shelf rather than the complete shelf. Only a complete shelf, not part of it, can be cleared, added to, repeated over, or saved.