editing a function definition

[SANDRA <LOOSEMORE@UTAH-20.ARPA>]

The manual says that doing (ed <symbol>) lets you edit the text for the
function named <symbol>, but it doesn't say what happens to it once you've
left the editor.  Is the definition replaced by whatever you did in the
editor?  If so, are other forms you added while in the editor evaluated
too?

Also, the manual leaves open the possibility of searching the file system
for the file containing the original definition of the function.  Does this
mean that the entire file may be passed to the editor, or should the
definition of that one function be extracted from the file instead?

-Sandra
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