Grass up old lag, getting time inside as such? (10)
I believe the answer is:
shoplifter
'time inside as such?' is the definition.
I can't judge whether this definition defines the answer.
'grass up old lag' is the wordplay.
'grass' becomes 'shop' (I've seen this before).
'up old lag' becomes 'lifter' (I am not sure about this - if you are sure you should believe this answer much more).
'shop'+'lifter'='SHOPLIFTER'
'getting' acts as a link.
Can you help me to learn more?
(Other definitions for shoplifter that I've seen before include "guilty party" , "Thieving customer" , "A petty criminal" , "Criminal (in a retail context)" , "Robber" .)