Redefining FISH Functions

A FISH function can be redefined. If a name that is already used for an existing function is given on a define line, the code corresponding to the old function is deleted (and a warning is printed) and the new code is substituted. The following are some notes of caution:

1. The variables used in a function still exist, even if the function is redefined; only the code is deleted. Since variables are global, it is likely that they are used elsewhere.
2. All calls to the old function will call the new function instead. This includes FISH callback events. Note that this will cause runtime errors if the number of arguments is changed.