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parenListLength

Class: matlab.mixin.indexing.RedefinesParen
Namespace: matlab.mixin.indexing

Determine number of values to return from customized indexing operations beginning with parentheses

Since R2021b

Syntax

n = parenListLength(obj,indexOp,indexContext)

Description

n = parenListLength(obj,indexOp,indexContext) determines the number of values to return from customized indexing operations that reference or assign to comma-separated lists. Operations that begin with parentheses indexing and end with dot or brace indexing produce comma-separated lists, such as [C{:}] = obj(idx).prop and [obj(idx).prop{:}] = B{:}. The IndexingOperation object contains the indices being changed, and indexContext identifies whether the reference is used in a statement, as a list of arguments to a function, or in an assignment operation.

Input Arguments

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Object that implements customized parentheses indexing by inheriting from matlab.mixin.indexing.RedefinesParen.

Types of indexing operations and indices referenced, specified as an array of IndexingOperation objects. For a parentheses reference, the first object in the array has a Type property of Paren

Context in which the indexing operation occurs, specified as one of these enumeration members:

  • matlab.indexing.IndexingContext.Statement — Indexed reference used as a statement (for example, obj.a)

  • matlab.indexing.IndexingContext.Expression — Indexed reference used as an argument to a function (for example, func(obj.a))

  • matlab.indexing.IndexingContext.Assignment — Indexed assignment (for example, obj.a = x).

Output Arguments

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Number of values to return from an indexing operation, specified as a nonnegative integer.

Attributes

Accessprotected
Abstracttrue

To learn about attributes of methods, see Method Attributes.

Examples

For a general framework that shows how to implement customized parentheses indexing, see matlab.mixin.indexing.RedefinesParen. For a runnable example of a mapping class that implements custom parentheses indexing, see Customize Parentheses Indexing for Mapping Class.

Version History

Introduced in R2021b