Change Signature

Refactoring with Change Signature is a convenient way to change the signature of a function, method or member variable. For C/C++, the refactoring changes both declaration and implementation, ensuring the two constructs remain consistent.

Changing signature is useful when a member type, method name, or parameter list becomes unclear or inadequate for meaningful use. The new signature makes a member or method more valuable to developers, and more likely to be used correctly.

You can change signature from an implementation, declaration or reference, allowing you to change without interrupting your normal flow of editing.

Hover over a method and select Change Signature from the refactoring menu.



A dialog with the current signature opens. Modify the signature to reflect your changes. Make sure your changes maintain proper syntax so Visual Assist X understands correctly what you intend to change. For example, change the name of a parameter so it is more meaningful.



Accept the new signature and your implementation is changed. For C/C++, the declaration and implementation are both changed so the constructs remain consistent.



If you change the name of a parameter, as in the example, all references to the parameter within the implementation are also changed.

Change Signature of Method

Change Signature on a method permits you to change all parts of a signature including:

• Method name
• Return type
• Visibility
• Parameter names
• Parameter types
• Parameter order
• Number of parameters
• Qualifiers

Changing a method name with Change Signature causes a dialog to open confirming an appropriate change of all references made to the original name. For example, change GetIT to GetItemText.



A dialog opens to confirm rename of references to GetIT.

Change Signature of Method: Return Type

Changing a return type does not change code accepting return values from references to the method. Instead, you must change all references appropriately to accept the new return type. Use Find References after Change Signature to locate the references.

For C/C++, changing return type or qualifiers changes both declaration and implementation.

Change Signature of Method: Parameters

You can change parameter names and types with Change Signature when invoked from the name of a method, i.e. not from one of the parameters. If you change parameter names, Visual Assist X assumes your order of parameters remains constant. If you keep parameter names the same, you can reorder them. If you need to change parameter names and parameter order, complete the refactoring by invoking Change Signature twice - change order in one refactoring and change names in the second.

For example, refactor in two steps to change parameters names and switch order from c, r to nRow, nCol. Begin by selecting Change Signature from the refactoring menu for the method.



Change the parameter names to nCol and nRow in the next dialog.



Accept the new signature and your code is changed. Since you renamed a parameter, references to that parameter within the implementation are changed as well.



In a second refactoring of the method, change the parameter order to nCol and nRow.



Accept the new signature and you notice the parameter list has changed but nothing within the implementation. Since this is C/C++, changes are made to both declaration and implementation.

Change Signature of Member Variable

In addition to changing signatures of methods, you can change the signature of local variables, member variables and parameters. Such refactoring is done typically from a reference to a variable, and only when the variable needs to be of a different type or visibility.

For C/C++, changing signature of a parameter to a method, not of the method itself, changes only the implementation. The declaration is untouched. Invoke Change Signature from the name of a method to change both the declaration and implementation.

Change Signature Does Not Change References

Change Signature does not change references to methods or member variables. A warning to this effect may appear if you make a significant change. For example, changing parameter order might require you to rearrange parameters in all references to a method.

Change references manually to accomodate the new signature. Use Find References after Change Signature to locate the references.

Miscellaneous

Change Signature is often invoked after Extract Method.

Change Signature is not available on symbols found using stable directories, e.g. from MFC or a 3rd party library.

Change Signature is not available on overloaded methods.

Change Signature is also available from the context menu in the Hovering Class Browser and VA Outline.

Change Signature does not modify signatures within comments. If signatures exist within comments, you must change them manually.

Use Change Signature on a method, instead of Rename, when modifying the name of a method or parameter.

Changing visibility is available only for C#.

Use UNDO to revert changes made to all files by Change Signature. (One UNDO reverts all changes when using VS2005 or VS.NET. Multiple UNDOs required when using VC++ 6.0.)

You can modify the format of signatures by editing the VA Snippets entries for Refactor Create Implementation.