TExprBuiltInManager class

In unit fpExprPars

Class for managing built-in functions and variables in expressions

Declaration

pascal

TExprBuiltInManager = class(TComponent)

Inheritance

TExprBuiltInManager
TComponent
TPersistent
TObject

Description

The TExprBuiltInManager class serves as a manager for built-in functions and predefined variables that can be used within expressions. It provides a centralized registry where built-in mathematical functions, string functions, date/time functions, and system variables are registered and made available to the expression parser.

The manager handles the registration, lookup, and instantiation of built-in functions when they are encountered during expression parsing. It also maintains predefined variables such as system constants that can be referenced in expressions.

The TExprBuiltInManager class allows for extensibility by enabling the registration of custom built-in functions and variables that should be available across all expression evaluations.

Properties

`Defs`	protected
`IdentifierCount`	public	Number of built-in identifiers
`Identifiers`	public	Array access to built-in identifiers

Methods

`Create`	public	Create built-in manager instance
`Destroy`	public	Destroy built-in manager instance
`IndexOfIdentifier`	public	Find index of built-in identifier
`FindIdentifier`	public	Find built-in identifier by name
`IdentifierByName`	public	Get identifier by name with exception on not found
`AddVariable`	public	Add variable to built-in collection
`AddBooleanVariable`	public	Add boolean variable to built-in collection
`AddIntegerVariable`	public	Add integer variable to built-in collection
`AddFloatVariable`	public	Add float variable to built-in collection
`AddCurrencyVariable`	public	Add currency variable to built-in collection
`AddStringVariable`	public	Add string variable to built-in collection
`AddDateTimeVariable`	public	Add datetime variable to built-in collection
`AddFunction`	public	Add function to built-in collection
`Delete`	public
`Remove`	public

Inherited

From TComponent (74)

_AddRef _Release BeforeDestruction CanObserve ChangeName ComObject ComponentCount ComponentIndex Components ComponentState ComponentStyle DefineProperties DesignInfo DestroyComponents Destroying ExecuteAction FindComponent FreeNotification FreeOnRelease GetChildOwner GetChildParent GetChildren GetDeltaStreams GetEnumerator GetIDsOfNames GetNamePath GetObservers GetOwner GetParentComponent GetTypeInfo GetTypeInfoCount HasParent iicrGetComponent InsertComponent Invoke IsImplementorOf Loaded Loading Name Notification ObserverAdded Observers OnGetDeltaStreams Owner PaletteCreated QueryInterface ReadDeltaState ReadDeltaStream ReadState ReferenceInterface RemoveComponent RemoveFreeNotification RemoveFreeNotifications SafeCallException SetAncestor SetChildOrder SetDesigning SetDesignInstance SetInline SetName SetParentComponent SetSubComponent Tag ToString TToStringNameMode UpdateAction Updated UpdateRegistry Updating ValidateContainer ValidateInsert ValidateRename VCLComObject WriteState

From TPersistent (5)

Assign AssignTo FPOAttachObserver FPODetachObserver FPONotifyObservers

From TObject (37)

AfterConstruction CheckDisposed ClassInfo ClassName ClassNameIs ClassParent ClassType CleanupInstance 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 StringMessageTable SystemHasExtendedRTTI UnitName

An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.