Class: QgsExpressionNodeLiteral¶

An expression node for literal values.

Note

This is an abstract class, with methods which must be implemented by a subclass.

The following methods must be implemented: QgsExpressionNode.needsGeometry()

Class Hierarchy¶

Base classes¶

QgsExpressionNode

Abstract base class for all nodes that can appear in an expression.

Methods

`value`	The value of the literal.
`valueAsString`	Returns a string representation of the node's literal value.

Virtual Methods

In PyQGIS, only methods marked as virtual can be safely overridden in a Python subclass of QgsExpressionNodeLiteral. See the FAQ for more details.

`evalNode`
`prepareNode`

class qgis.core.QgsExpressionNodeLiteral[source]¶

Bases: QgsExpressionNode

__init__(value: Any)

Constructor for QgsExpressionNodeLiteral, with the specified literal value.

Parameters:: value (Any)

__init__(a0: QgsExpressionNodeLiteral)

Parameters:: a0 (QgsExpressionNodeLiteral)

virtual evalNode(self, parent: QgsExpression | None, context: QgsExpressionContext | None) → Any[source]¶

Parameters:

parent (Optional[QgsExpression])
context (Optional[QgsExpressionContext])

Return type:

Any

virtual prepareNode(self, parent: QgsExpression | None, context: QgsExpressionContext | None) → bool[source]¶

Parameters:

parent (Optional[QgsExpression])
context (Optional[QgsExpressionContext])

Return type:

bool

value(self) → Any[source]¶

The value of the literal.

Return type:: Any

valueAsString(self) → str[source]¶

Returns a string representation of the node’s literal value.

Added in version 3.20.

Return type:: str