Illegal source operation.
#2000 Compile-time error
Illegal source operation.
Additional Information
The 'IS ATTACHED' test cannot be applied to the MARKUP SOURCE 'X'.
A stream type test cannot be applied to the VALUE STRING SOURCE argument 'X'.
Source 'X' is not available when NO-DEFAULT-IO is declared.
where X is the name of an OmniMark pre-defined source.
Recovery
Compilation continues but no compiled source code file will be saved.
Explanation
This error is emitted whenever an operation is encountered which is
not applicable to the source to which it is being applied.