"rehash" each time a new program is installed?

[Louis-David Mitterrand <cunctator@xxxxxxxxxx>]

Hello,

I find myself having to run "rehash" to get zsh to recognize the
presence of a new executable in the PATH. bash doesn't seem to have that
requirement. Is there an option to get that behavior in zsh?

Also, how could I have zsh not list "CVS" directories when completing
paths? I tried fignore but it doesn't work.

Oh, and a last one ;) Is it possible to "fignore" a file except when
it's the only completion candidate (considering the typed string e.g.)?

Thanks in advance,

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