Subgroup: other

Class: QgsScopedExpressionFunction

class qgis.core.QgsScopedExpressionFunction

Bases: qgis._core.QgsExpressionFunction

Expression function for use within a QgsExpressionContextScope. This differs from a standard QgsExpression.Function in that it requires an implemented clone() method.

New in version 2.12: Methods

aliases	Returns a list of possible aliases for the function.
allParamsStatic
clone	Returns a clone of the function.
func
group	Returns the first group which the function belongs to.
groups	Returns a list of the groups the function belongs to.
handlesNull
helpText	The help text for the function.
isContextual	Returns whether the function is only available if provided by a QgsExpressionContext object.
isDeprecated	Returns true if the function is deprecated and should not be presented as a valid option to users in expression builders.
isStatic
lazyEval	True if this function should use lazy evaluation.
minParams	The minimum number of parameters this function takes.
name	The name of the function.
parameters	Returns the list of named parameters for the function, if set.
params	The number of parameters this function takes.
prepare	This will be called during the prepare step() of an expression if it is not static.
referencedColumns
run
usesGeometry

Attributes

allParamsStatic()

clone(self) → QgsScopedExpressionFunction

Returns a clone of the function.

func(self, values: List[Any], context: QgsExpressionContext, parent: QgsExpression, node: QgsExpressionNodeFunction) → Any

isStatic(self, node: QgsExpressionNodeFunction, parent: QgsExpression, context: QgsExpressionContext) → bool

referencedColumns(self, node: QgsExpressionNodeFunction) → Set[str]

usesGeometry(self, node: QgsExpressionNodeFunction) → bool