defineArgument

R2026b

Class: clibgen.ConstructorDefinition
Namespace: clibgen

(Not recommended) Add input argument definition for C++ constructor

defineArgument is not recommended. For more information on updating your code, see Version History.

Syntax

defineArgument(ConstructorDefinition,CPPName,MATLABType)

defineArgument(ConstructorDefinition,CPPName,MATLABType,Direction)

defineArgument(ConstructorDefinition,CPPName,MATLABType,Direction,Shape)

defineArgument(___,Name=Value)

Description

defineArgument(ConstructorDefinition,CPPName,MATLABType) adds an input argument definition for a C++ constructor.

defineArgument(ConstructorDefinition,CPPName,MATLABType,Direction) defines whether argument is input, output, or both.

defineArgument(ConstructorDefinition,CPPName,MATLABType,Direction,Shape) provides information about data dimensions.

defineArgument(___,Name=Value) adds additional argument definition options specified by one or more name-value arguments, and can include any of the input parameters in previous syntaxes.

Input Arguments

ConstructorDefinition — Constructor definition

clibgen.ConstructorDefinition

Constructor definition, specified as a clibgen.ConstructorDefinition object.

CPPName — C++ argument name

string scalar | character vector

C++ argument name, specified as a string scalar or a character vector and is used with the Description name-value argument.

MATLABType — MATLAB type

string scalar | character vector

MATLAB^® type, specified as a string scalar or a character vector.

Direction — Argument type

"input" (default) | "output" | "inputoutput"

Argument type, specified as "input" for an input argument, "output" for an output argument, or "inputoutput" for both an input and an output argument.

Shape — Information for defining data dimensions

string vector | scalar text | positive integer vector | "nullTerminated" | cell array

Dimension definition used by MATLAB to define data dimensions, specified as a string vector, scalar text, positive integer vector, "nullTerminated", or a cell array. For a cell array, the elements are a combination of scalar text and scalar positive integers. For more information, see Define Missing Size Property.

If you can define the argument dimension as a fixed scalar value, then enter a number, such as 5.

If the dimension is defined by another argument, then enter the argument name as a string. For example, consider the following C++ signature. If argument len defines the length of data, then the value of Shape is "len".

myFunc(const int *data, int len)

If the size of an argument is defined by an array, then the value of Shape is one of the following:

• 1

• Fixed dimensions: Enter a numerical array, such as [5,2].

• Variable dimensions: Enter a string array of parameter names, such as ["row","col"].

If the C++ type for the argument is a string, then use these options to choose values for the MATLABType and Shape arguments.

C++ Type	MATLABType	Direction	Options for Size
char*a	"int8"	"input"	Scalar value Array of scalar values
char** char*[]	"string"	"input"	cell
const char*	"char"		Scalar value Array of scalar values
	"string"	"input"	"nullTerminated"
const char** const char*[]	"char"	"input"	Scalar value Array of scalar values
	"string"	"input"	"nullTerminated"
a These types are equivalent to MATLAB char: wchar_t char16_t char32_t

For more information, see C++ to MATLAB Data Type Mapping.

Name-Value Arguments

Specify optional pairs of arguments as Name1=Value1,...,NameN=ValueN, where Name is the argument name and Value is the corresponding value. Name-value arguments must appear after other arguments, but the order of the pairs does not matter.

Description — C++ argument description

string scalar | character vector

C++ argument description, specified as a string scalar or a character vector. This value sets the Description property.

ReleaseOnCall — Transfer memory ownership of argument

false or 0 (default) | true or 1

Transfer memory ownership of argument, specified as a numeric or logical 1 (true) or 0 (false). MATLAB owns memory that is allocated as a pointer or a reference for an input argument. The C++ library should not free this memory. To change this behavior for a non-const argument, set ReleaseOnCall to true.

The ReleaseOnCall argument is not supported for:

• const arguments.

• Double pointer (obj** or void**) arguments defined as output.

If ReleaseOnCall is not specified, then ReleaseOnCall is false.

For more information, see Lifetime Management of C++ Objects in MATLAB.

AddTrailingSingletons — Where to pad dimensions

false or 0 (default) | true or 1

Where to pad dimensions, specified as a numeric or logical 1 (true) or 0 (false). By default, when a MATLAB input has fewer dimensions than the corresponding C++ argument, then MATLAB inserts singleton dimensions at the beginning of the Shape argument. To insert singleton dimensions at the end, set AddTrailingSingletons to true. For more information , see Dimension Matching.

Example: AddTrailingSingletons=true

Data Types: logical

Version History

Introduced in R2019a

R2026b: Not recommended

There are no plans to remove defineArgument. However, creating a clibgen.api.InterfaceDefinition object in the clibgen.api namespace is recommended instead.