Function Precedence Order
This topic explains how MATLAB® determines which function to call when multiple functions in the current scope have the same name. The current scope includes the current file, an optional private subfolder relative to the currently running function, the current folder, and the MATLAB path.
MATLAB uses this precedence order:
Before assuming that a name matches a function, MATLAB checks for a variable with that name in the current workspace.
If you create a variable with the same name as a function, MATLAB cannot run that function until you clear the variable from memory.
Function or class whose name matches an explicitly imported name
importfunction allows functions with compound names (names comprised of several parts joined by dots) to be called using only the final part of the compound name. When a function name matches an explicit (non-wildcard) imported function, MATLAB uses the imported compound name and gives it precedence over all other functions with the same name.
Nested functions within the current function
Local functions within the current file
Function or class whose name matches a wildcard-based imported name
When a function name matches a wildcard-based imported function, MATLAB uses the imported compound name and gives it precedence over all other functions with the same name, except for nested and local functions.
Private functions are functions in a subfolder named
privatethat is immediately below the folder of the currently running file.
An object function accepts a particular class of object in its input argument list. When there are multiple object functions with the same name, MATLAB checks the classes of the input arguments to determine which function to use.
Class constructors in @ folders
MATLAB uses class constructors to create a variety of objects (such as
audioplayer), and you can define your own classes using object-oriented programming. For example, if you create a class folder
@polynomand a constructor function
@polynom/polynom.m, the constructor takes precedence over other functions named
polynom.manywhere on the path.
Loaded Simulink® models
Functions in the current folder
Functions elsewhere on the path, in order of appearance
When determining the precedence of functions within the same folder, MATLAB considers the file type, in this order:
Simulink model files that are not loaded, with file types in this order:
Stateflow® chart with a
App file (
.mlapp) created using MATLAB App Designer
Program file with a
P-file (that is, an encoded program file with a
Program file with a
For example, if MATLAB finds a
.m file and a P-file with the same name in the
same folder, it uses the P-file. Because P-files are not automatically regenerated, make
sure that you regenerate the P-file whenever you edit the program file.
To determine the function MATLAB calls for a particular input, include the function name and the input in a
call to the
Change in Rules For Function Precedence Order
Starting in R2019b, MATLAB changes the rules for name resolution, impacting the precedence order of variables, nested functions, local functions, and external functions. For information about the changes and tips for updating your code, see Update Code for R2019b Changes to Function Precedence Order.
Identifiers cannot be used for two purposes inside a function
Identifiers without explicit declarations might not be treated as variables
Variables cannot be implicitly shared between parent and nested functions
Change in precedence of compound name resolution
Anonymous functions can include resolved and unresolved identifiers
The behavior of the
import function has changed.
Change in precedence of wildcard-based imports
Fully qualified import functions cannot have the same name as nested functions
Fully qualified imports shadow outer scope definitions of the same name
Error handling when import not found
Nested functions inherit import statements from parent functions