mirror of
https://github.com/qgis/QGIS.git
synced 2025-10-08 00:05:09 -04:00
270 lines
8.9 KiB
Plaintext
270 lines
8.9 KiB
Plaintext
/************************************************************************
|
|
* This file has been generated automatically from *
|
|
* *
|
|
* src/core/expression/qgsexpressionfunction.h *
|
|
* *
|
|
* Do not edit manually ! Edit header and run scripts/sipify.pl again *
|
|
************************************************************************/
|
|
|
|
|
|
|
|
|
|
|
|
|
|
class QgsExpressionFunction
|
|
{
|
|
%Docstring(signature="appended")
|
|
A abstract base class for defining :py:class:`QgsExpression` functions.
|
|
%End
|
|
|
|
%TypeHeaderCode
|
|
#include "qgsexpressionfunction.h"
|
|
%End
|
|
public:
|
|
|
|
|
|
class Parameter
|
|
{
|
|
%Docstring(signature="appended")
|
|
Represents a single parameter passed to a function.
|
|
%End
|
|
|
|
%TypeHeaderCode
|
|
#include "qgsexpressionfunction.h"
|
|
%End
|
|
public:
|
|
|
|
Parameter( const QString &name,
|
|
bool optional = false,
|
|
const QVariant &defaultValue = QVariant(),
|
|
bool isSubExpression = false );
|
|
%Docstring
|
|
Constructor for Parameter.
|
|
|
|
:param name: parameter name, used when named parameter are specified in an expression
|
|
:param optional: set to ``True`` if parameter should be optional
|
|
:param defaultValue: default value to use for optional parameters
|
|
:param isSubExpression: set to ``True`` if this parameter is a sub-expression
|
|
%End
|
|
|
|
QString name() const;
|
|
%Docstring
|
|
Returns the name of the parameter.
|
|
%End
|
|
|
|
bool optional() const;
|
|
%Docstring
|
|
Returns ``True`` if the parameter is optional.
|
|
%End
|
|
|
|
QVariant defaultValue() const;
|
|
%Docstring
|
|
Returns the default value for the parameter.
|
|
%End
|
|
|
|
bool isSubExpression() const;
|
|
%Docstring
|
|
Returns ``True`` if parameter argument is a separate sub-expression, and
|
|
should not be checked while determining referenced columns for the expression.
|
|
|
|
.. versionadded:: 3.2
|
|
%End
|
|
|
|
bool operator==( const QgsExpressionFunction::Parameter &other ) const;
|
|
|
|
};
|
|
|
|
typedef QList< QgsExpressionFunction::Parameter > ParameterList;
|
|
|
|
QgsExpressionFunction( const QString &fnname,
|
|
int params,
|
|
const QString &group,
|
|
const QString &helpText = QString(),
|
|
bool lazyEval = false,
|
|
bool handlesNull = false,
|
|
bool isContextual = false );
|
|
%Docstring
|
|
Constructor for function which uses unnamed parameters
|
|
%End
|
|
|
|
QgsExpressionFunction( const QString &fnname,
|
|
int params,
|
|
const QStringList &groups,
|
|
const QString &helpText = QString(),
|
|
bool lazyEval = false,
|
|
bool handlesNull = false,
|
|
bool isContextual = false );
|
|
%Docstring
|
|
Constructor for function which uses unnamed parameters and group list
|
|
%End
|
|
|
|
QgsExpressionFunction( const QString &fnname,
|
|
const QgsExpressionFunction::ParameterList ¶ms,
|
|
const QString &group,
|
|
const QString &helpText = QString(),
|
|
bool lazyEval = false,
|
|
bool handlesNull = false,
|
|
bool isContextual = false );
|
|
%Docstring
|
|
Constructor for function which uses named parameter list.
|
|
%End
|
|
|
|
QgsExpressionFunction( const QString &fnname,
|
|
const QgsExpressionFunction::ParameterList ¶ms,
|
|
const QStringList &groups,
|
|
const QString &helpText = QString(),
|
|
bool lazyEval = false,
|
|
bool handlesNull = false,
|
|
bool isContextual = false );
|
|
%Docstring
|
|
Constructor for function which uses named parameter list and group list.
|
|
%End
|
|
|
|
virtual ~QgsExpressionFunction();
|
|
|
|
QString name() const;
|
|
%Docstring
|
|
The name of the function.
|
|
%End
|
|
|
|
int params() const;
|
|
%Docstring
|
|
The number of parameters this function takes.
|
|
%End
|
|
|
|
int minParams() const;
|
|
%Docstring
|
|
The minimum number of parameters this function takes.
|
|
%End
|
|
|
|
const QgsExpressionFunction::ParameterList ¶meters() const;
|
|
%Docstring
|
|
Returns the list of named parameters for the function, if set.
|
|
%End
|
|
|
|
virtual bool usesGeometry( const QgsExpressionNodeFunction *node ) const;
|
|
%Docstring
|
|
Does this function use a geometry object.
|
|
%End
|
|
|
|
virtual QStringList aliases() const;
|
|
%Docstring
|
|
Returns a list of possible aliases for the function. These include
|
|
other permissible names for the function, e.g., deprecated names.
|
|
|
|
:return: list of known aliases
|
|
%End
|
|
|
|
bool lazyEval() const;
|
|
%Docstring
|
|
``True`` if this function should use lazy evaluation. Lazy evaluation functions take :py:class:`QgsExpression`.Node objects
|
|
rather than the node results when called. You can use node->eval(parent, feature) to evaluate the node and return the result
|
|
Functions are non lazy default and will be given the node return value when called.
|
|
%End
|
|
|
|
virtual bool isStatic( const QgsExpressionNodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context ) const;
|
|
%Docstring
|
|
Will be called during prepare to determine if the function is static.
|
|
A function is static if it will return the same value for every feature with different
|
|
attributes and/or geometry.
|
|
|
|
By default this will return ``True``, if all arguments that have been passed to the function
|
|
are also static.
|
|
%End
|
|
|
|
virtual bool prepare( const QgsExpressionNodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context ) const;
|
|
%Docstring
|
|
This will be called during the prepare :py:func:`~QgsExpressionFunction.step` of an expression if it is not static.
|
|
|
|
This can be used by functions to do any preparation steps that might help to speedup the upcoming
|
|
evaluation.
|
|
%End
|
|
|
|
virtual QSet<QString> referencedColumns( const QgsExpressionNodeFunction *node ) const;
|
|
%Docstring
|
|
Returns a set of field names which are required for this function.
|
|
May contain :py:class:`QgsFeatureRequest`.AllAttributes to signal that all
|
|
attributes are required.
|
|
If in doubt this will return more fields than strictly required.
|
|
%End
|
|
|
|
bool isContextual() const;
|
|
%Docstring
|
|
Returns whether the function is only available if provided by a :py:class:`QgsExpressionContext` object.
|
|
%End
|
|
|
|
virtual bool isDeprecated() const;
|
|
%Docstring
|
|
Returns ``True`` if the function is deprecated and should not be presented as a valid option
|
|
to users in expression builders.
|
|
%End
|
|
|
|
QString group() const;
|
|
%Docstring
|
|
Returns the first group which the function belongs to.
|
|
|
|
.. note::
|
|
|
|
consider using :py:func:`~QgsExpressionFunction.groups` instead, as some functions naturally belong in multiple groups
|
|
%End
|
|
|
|
QStringList groups() const;
|
|
%Docstring
|
|
Returns a list of the groups the function belongs to.
|
|
|
|
.. seealso:: :py:func:`group`
|
|
%End
|
|
|
|
const QString helpText() const;
|
|
%Docstring
|
|
The help text for the function.
|
|
%End
|
|
|
|
virtual QVariant func( const QVariantList &values, const QgsExpressionContext *context, QgsExpression *parent, const QgsExpressionNodeFunction *node ) = 0;
|
|
%Docstring
|
|
Returns result of evaluating the function.
|
|
|
|
:param values: list of values passed to the function
|
|
:param context: context expression is being evaluated against
|
|
:param parent: parent expression
|
|
:param node: expression node
|
|
|
|
:return: result of function
|
|
%End
|
|
|
|
virtual QVariant run( QgsExpressionNode::NodeList *args, const QgsExpressionContext *context, QgsExpression *parent, const QgsExpressionNodeFunction *node );
|
|
%Docstring
|
|
Evaluates the function, first evaluating all required arguments before passing them to the
|
|
function's :py:func:`~QgsExpressionFunction.func` method.
|
|
%End
|
|
|
|
bool operator==( const QgsExpressionFunction &other ) const;
|
|
|
|
virtual bool handlesNull() const;
|
|
%Docstring
|
|
Returns ``True`` if the function handles NULL values in arguments by itself, and the default
|
|
NULL value handling should be skipped.
|
|
%End
|
|
|
|
protected:
|
|
|
|
static bool allParamsStatic( const QgsExpressionNodeFunction *node, QgsExpression *parent, const QgsExpressionContext *context );
|
|
%Docstring
|
|
This will return ``True`` if all the params for the provided function ``node`` are static within the
|
|
constraints imposed by the ``context`` within the given ``parent``.
|
|
|
|
This can be used as callback for custom implementations of subclasses. It is the default for implementation
|
|
for StaticFunction.isStatic.
|
|
%End
|
|
|
|
};
|
|
|
|
|
|
/************************************************************************
|
|
* This file has been generated automatically from *
|
|
* *
|
|
* src/core/expression/qgsexpressionfunction.h *
|
|
* *
|
|
* Do not edit manually ! Edit header and run scripts/sipify.pl again *
|
|
************************************************************************/
|