| ActiveTcl User Guide |

## Tcl/Tk Documentation > TclCmd > rename

### Tcl/Tk Applications | Tcl Commands | Tk Commands | Tcl Library | Tk Library

### NAME

rename - Rename or delete a command

### SYNOPSIS

rename oldName newName

### DESCRIPTION

Rename the command that used to be called oldName so that it is now called newName. If newName is an empty string then oldName is deleted. oldName and newName may include namespace qualifiers (names of containing namespaces). If a command is renamed into a different namespace, future invocations of it will execute in the new namespace. The rename command returns an empty string as result.

### EXAMPLE

The rename command can be used to wrap the standard Tcl commands with your own monitoring machinery. For example, you might wish to count how often the source command is called:

    rename ::source ::theRealSource
    set sourceCount 0
    proc ::source args {
        global sourceCount
        puts "called source for the [incr sourceCount]'th time"
        uplevel 1 ::theRealSource $args
    }

### SEE ALSO

namespace, proc

### KEYWORDS

command, delete, namespace, rename
Copyright © 1995-1997 Roger E. Critchlow Jr. Copyright © 1993 The Regents of the University of California. Copyright © 1994-1997 Sun Microsystems, Inc.