sheet->catch

Documentation
- Reference manual
- Packages
  - XPCE
    - Classes
      - class sheet
        
        Send methods
        
        sheet->append
        
        sheet->catch_all
        
        sheet->delete
        
        sheet->for_some
        
        sheet->for_all
        
        sheet->initialise
        
        sheet->value

sheet ->catch_all: key=name, value=any

The methods sheet<->catch_all are called by PCE's message-passing system if there is no other definition for a method. Class sheet uses these methods to store and fetch attributes:

?- new(@s, sheet(name, age, address)),
   send(@s, name, gnu).

?- get(@s, name, X).

   X = gnu

This approach has, besides its definite charm, one drawbacks: Attributes whose name collide with a method name cannot be accessed this way. Code that handles unknown attribute names should use sheet<->value to avoid this problem.