Possible Feature Requests (unsource, exchange)

[Christopher Roy Bratusek]

Hi all,

what I'm currently missing are the following two things (I'm not 100%
sure if they are not available):

unsource: the opposite of source (while source is making functions
publically available, unsource would remove them) 

exchange: exchanges the value of two variables (x=2 y=a; exchange x y;
x=a y=2 -- need to be exported, so $1 $2 inside a function/script don't
help that much)

echo no-expand: if you do echo $@ ($@ is $x $y for example) echo will
print the values of $x $y instead of simply $x and $y is there a way to
achieve this?

I don't rely on this to be in bash itself, if someone can point me to
the right way to write scripts contaning those functions, it o.k., too.

Thanks for reading,
Chris