Class: QgsExpressionNodeFunction

class qgis.core.QgsExpressionNodeFunction(fnIndex: int, args: QgsExpressionNode.NodeList)

Bases: QgsExpressionNode

A function node consists of an index of the function in the global function array and a list of arguments that will be passed to it.

QgsExpressionNodeFunction(QgsExpressionNodeFunction)

An expression node for expression functions.

Parameters
  • fnIndex (int) –

  • args

args(self)QgsExpressionNode.NodeList

Returns a list of arguments specified for the function.

Return type

QgsExpressionNode.NodeList

clone(self)QgsExpressionNode
Return type

QgsExpressionNode

dump(self) → str
Return type

str

evalNode(self, parent: QgsExpression, context: QgsExpressionContext) → Any
Parameters
Return type

Any

fnIndex(self) → int

Returns the index of the node’s function.

Return type

int

isStatic(self, parent: QgsExpression, context: QgsExpressionContext) → bool
Parameters
Return type

bool

nodeType(self)QgsExpressionNode.NodeType
Return type

QgsExpressionNode.NodeType

prepareNode(self, parent: QgsExpression, context: QgsExpressionContext) → bool
Parameters
Return type

bool

referencedColumns(self) → Set[str]
Return type

Set[str]

referencedFunctions(self) → Set[str]
Return type

Set[str]

referencedVariables(self) → Set[str]
Return type

Set[str]

validateParams(fnIndex: int, args: QgsExpressionNode.NodeList, error: str) → bool

Tests whether the provided argument list is valid for the matching function

Parameters
Return type

bool