TFPFunctionCallBack class
Internally used class for callback-based function expressions
Declaration
TFPFunctionCallBack = class(TFPExprFunction)Inheritance
- TFPFunctionCallBack
- TFPExprFunction
- TFPExprIdentifierNode
- TFPExprNode
- TObject
Description
The TFPFunctionCallBack class implements function calls that are resolved using callback mechanisms rather than built-in function implementations.
It extends the expression framework to allow dynamic function resolution through user-defined callback procedures.
The callback function mechanism enables applications to provide custom function implementations that can be called from within expressions. This allows for extending the expression language with application-specific functions without modifying the core expression parser.
When a callback function is called, the registered callback procedure is invoked with the function arguments and is expected to compute and return the function result.
See also
Properties
CallBack | public | The callback procedure for function evaluation |
Methods
CreateFunction | public | Create callback function with identifier and arguments |
GetNodeValue | public | Get callback function result |
Inherited
From TFPExprFunction (10)
ArgumentNodes ArgumentParams AsString CalcParams Check ConvertArgument Destroy HasAggregate InitAggregate UpdateAggregate
From TFPExprIdentifierNode (3)
From TFPExprNode (3)
From TObject (41)
AfterConstruction BeforeDestruction CheckDisposed ClassInfo ClassName ClassNameIs ClassParent ClassType CleanupInstance Create DefaultHandler DefaultHandlerStr Dispatch DispatchStr Disposed DisposeOf Equals FieldAddress Free FreeInstance GetDisposed GetHashCode GetInterface GetInterfaceByStr GetInterfaceEntry GetInterfaceEntryByStr GetInterfaceTable GetInterfaceWeak GetLastCastErrorInfo InheritsFrom InitInstance InstanceSize MethodAddress MethodName newinstance QualifiedClassName SafeCallException StringMessageTable SystemHasExtendedRTTI ToString UnitName
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.