Hello--
In the process of writing the command-line app that goes with the sass egg, I noticed an issue with the args egg. I don't know if this is necessarily a bug - maybe just an awkward feature.
Anyway, it seems that if you specify an option with no arguments, e.g.
(args:make-option (v version) #:none
"Display compiled versions.")
... then when the user invokes the program with that option, you get:
'((v . #f) (version . #f))
... which means that alist-ref will not tell you whether the user passed that option, or it simply isn't present. I wonder if it wouldn't be better for a no-arg option to produce a symbol, #:undefined perhaps?
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