Cpp.Variable Class

Namespace: Cpp
Superclasses: ObjectWithPosition

Represents a variable in your code

Since R2026a

Description

Variable class represents variables in your code. This class inherits from the class ObjectWithPosition. You can use the predicates associated with this class and the base class with objects of this object.

Predicates

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Types

You can report a defect on Raisable types. If a type is Printable, it can be reported in the message. For Variable objects, print the string obtained by the predicate Cpp.Variable.name.

Type	Raisable	Printable
`Lang.Int`	No	Yes
`Lang.String`	No	Yes
`Variable`	Yes	No

Syntaxes

This class defines these predicates that act on the Variable objects. In addition, objects of Variable class can access the predicates defined by the base class ObjectWithPosition. An object of Variable class is an object of ObjectWithPosition class.

Predicates	Description
`is(Variable &variable)`	Retrieves all Variable objects in your code.
`name(Variable self, Lang.String &name)`	Retrieves the name of the variable self and stores it in name.
`isUnnamed(Variable self)`	Retrieves Variable objects that are unnamed.
`qualifiedName(Variable self, Lang.String &name)`	Retrieves the fully qualified name of the variable self and stores it in name.
`type(Variable self, Cpp.Type.Type &type)`	Retrieves the type of the variable self and stores it in type.
`namespace(Variable self, Cpp.Namespace.Namespace &namespace)`	Retrieves the namespace in which the variable self is declared and stores it in namespace.
`isGloballyVisible(Variable self)`	Retrieves variables that have global visibility (not static or local).
`isFileStatic(Variable self)`	Retrieves variables that are file-static (declared with static at file scope).
`isFunctionNonStaticLocal(Variable self)`	Retrieves variables that are local to a function and not declared static.
`isFunctionParameter(Variable self)`	Retrieves variables that are function parameters.
`isFunctionStaticLocal(Variable self)`	Retrieves variables that are static locals in a function.
`isClassStatic(Variable self)`	Retrieves variables that are static members of a class.
`isDefined(Variable self)`	Retrieves variables that are defined (not just declared).
`isDeclaredAuto(Variable self)`	Retrieves variables that are declared with the auto keyword.
`isConstexpr(Variable self)`	Retrieves variables that are declared as constexpr.
`isInitializedAtDeclaration(Variable self)`	Retrieves variables that are initialized at declaration.

Examples

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Unused member variable in header file

In a new folder Field, initialize a new coding standard. At the command line, enter:
```
polyspace-query-language init
```

In the file main.pql, enter this content:

package main

// Main PQL file defines the catalog of your PQL project.
// The catalog is a collection of sections.
catalog FieldExample = {
#[Description("Example Section")]
	section ExampleSection = {
#[Description("Unused public field in header"),Id(myRule)]
		rule ExampleRule = {
			defect Exampledefect =
			when			
				Cpp.Field.is(&field)
				and field.isUnused()
				and field.isPublic()
				and field.extension(&ext)
				and ext == ".h"
				and field.filename(&fnstr)
			raise "Unused public field in header: \"{fnstr}\""
			on field

		}
	}
}

Create the coding standard Field.pschk using this command at the command line:
```
polyspace-query-language package
```
Using the generated coding standard, run a Bug Finder analysis on your source file. Foe example, at the command line, enter:
```
polyspace-bug-finder -sources src.cpp -lang cpp -checkers-activation-file Field.pschk
```
The analysis reports defects on the unused member variable unusedField in the header file src.h.

Version History

Introduced in R2026a