While gas sold regularly, using it? (2,4,2)

I believe the answer is:
as long as
'while' is the definition.
(I've seen this in another clue)
'gas sold regularly using it?' is the wordplay.
'regularly' means one should take alternating letters (regularly take one letter, leave next etc.).
'using' becomes 'on' (someone using drugs is 'on' them).
'it?' becomes 'gas' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'gas'+'sold'='gassold'
The alternate letters of 'gassold' are 'asl'.
'asl'+'on'+'gas'='AS LONG AS'
Can you help me to learn more?
(Other definitions for as long as that I've seen before include "On condition that - (" ___ your arm")" , "Provided" , "for the time" .)