MBVariableDeclaration Class Reference
Inherits from | MBDataModel : MBFormattedDescriptionObject |
---|---|
Declared in | MBVariableDeclaration.h |
Overview
A partially-implemented root class that represents a variable declared in MBML.
The MBConcreteVariableDeclaration
, MBSingletonVariableDeclaration
, and
MBDynamicVariableDeclaration
classes provide specific implementations.
Variable information
name
Returns the name of the variable.
@property (nullable, nonatomic, readonly) NSString *name
Declared In
MBVariableDeclaration.h
isReadOnly
Returns YES
if the variable contains a read-only value.
@property (nonatomic, readonly) BOOL isReadOnly
Declared In
MBVariableDeclaration.h
disallowsValueCaching
Returns YES
if the variable’s value should not be cached by the
MBVariableSpace
. By definition, such variables are also read-only.
@property (nonatomic, readonly) BOOL disallowsValueCaching
Declared In
MBVariableDeclaration.h
Accessing variable values
– initialValueInVariableSpace:error:
Returns the initial value of the variable in the given variable space.
- (nullable id)initialValueInVariableSpace:(nonnull MBVariableSpace *)space error:(MBExpressionErrorPtrPtr)errPtr
Parameters
space |
The |
---|---|
errPtr |
If non- |
Discussion
Note: This method should not be called for variables whose
disallowsValueCaching
property returns YES
; in such
cases, an exception is raised.
Declared In
MBVariableDeclaration.h
– currentValueInVariableSpace:error:
Returns the current value of the variable in the given variable space.
- (nullable id)currentValueInVariableSpace:(nonnull MBVariableSpace *)space error:(MBExpressionErrorPtrPtr)errPtr
Parameters
space |
The |
---|---|
errPtr |
If non- |
Declared In
MBVariableDeclaration.h
Variable value change hook
– valueChangedTo:inVariableSpace:
Called when a mutable variable value has changed.
- (void)valueChangedTo:(nullable id)value inVariableSpace:(nonnull MBVariableSpace *)space
Parameters
value |
The new value of the variable. |
---|---|
space |
The |
Declared In
MBVariableDeclaration.h