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Change Signature Dialog for JavaScript

Refactor | Change Signature

Use this dialog to change the function signature and to perform other related tasks.




Use this field to modify the function name.

Use the table and the controls to the right of it to manage the function parameters and their properties.


Use this field to specify the name of a parameter.


A parameter value.

If the parameter is a required one, the specified value (or expression) will be passed to the function in the function calls. If the parameter is an optional one, this value will be used in the function body to initialize the parameter.


Select this checkbox if the parameter is optional. Your selection will define how the parameter value is used.

icons general add svg or Alt+Insert

Use this icon or shortcut to start adding a new parameter.

Specify the parameter name and value. Also, specify whether the parameter is optional.

Note that you can propagate the parameters you have added to the calling methods.

icons general remove svg or Alt+Delete

Use this icon or shortcut to delete the selected parameter.

icons actions previousOccurence svg or Alt+Up

Use this icon or shortcut to move the selected parameter one line up in the list of parameters.

icons actions nextOccurence svg or Alt+Down

Use this icon or shortcut to move the selected parameter one line down in the list of parameters.


Use this icon or shortcut to propagate the added parameters to the calling methods.

You can propagate new function parameters to any function that directly or indirectly calls the function whose signature you are changing.

(There may be the functions that call the current function. These functions, in their turn, may be called by other functions. You can propagate new parameters to any of the functions in such sequences.)

In the left-hand pane of the Select Methods to Propagate New Parameters dialog, expand the necessary nodes and select the checkboxes next to the functions you want the new parameters to be propagated to.

Signature Preview

In this area, the current function signature is shown. (The information in this area is synchronized with the changes you are making to the function signature.)


Click this button to perform the refactoring right away.


Click this button to see the expected changes prior to actually performing the refactoring.

Last modified: 19 November 2018

See Also