Class: QgsExpressionNodeFunction

class qgis.core.QgsExpressionNodeFunction

Bases: QgsExpressionNode

An expression node for expression functions.

QgsExpressionNodeFunction(fnIndex: int, args: Optional[QgsExpressionNode.NodeList]) 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(a0: QgsExpressionNodeFunction)

Methods

args

Returns a list of arguments specified for the function.

clone

rtype:

Optional[QgsExpressionNode]

dump

rtype:

str

evalNode

param parent:

fnIndex

Returns the index of the node's function.

isStatic

param parent:

nodeType

rtype:

QgsExpressionNode.NodeType

prepareNode

param parent:

referencedColumns

rtype:

Set[str]

referencedFunctions

rtype:

Set[str]

referencedVariables

rtype:

Set[str]

validateParams

Tests whether the provided argument list is valid for the matching function
args(self) → QgsExpressionNode.NodeList | None

Returns a list of arguments specified for the function.

Return type:

Optional[QgsExpressionNode.NodeList]

clone(self) → QgsExpressionNode | None
Return type:

Optional[QgsExpressionNode]

dump(self) → str
Return type:

str

evalNode(self, parent: QgsExpression | None, context: QgsExpressionContext | None) → Any
Parameters:
Return type:

Any

fnIndex(self) → int

Returns the index of the node’s function.

Return type:

int

isStatic(self, parent: QgsExpression | None, context: QgsExpressionContext | None) → bool
Parameters:
Return type:

bool

nodeType(self) → QgsExpressionNode.NodeType
Return type:

QgsExpressionNode.NodeType

prepareNode(self, parent: QgsExpression | None, context: QgsExpressionContext | None) → 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 | None, error: str | None) → bool

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

Parameters:
Return type:

bool