terminal and vim as external editor

Hello,

New Ada and GNAT-GPS user here...

I've installed GNAT-GPS 5.0-14 (latest on Debian Sid x86_64) and try to
use vim as external editor.

Have two questions:

a) is it possible to teach GPS to use some other editor except xterm (I
regularly use rxvt-unicode)?

b) I set Vim as external editor, but it does not launch? Any hint?


Sincerely,
Gour

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