Like one on the wagon missing having can inside (9)

I believe the answer is:

abstinent

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'like one on the wagon' is the definition.
(a recovering alcoholic or addict is 'on the wagon')

'missing having can inside' is the wordplay.
'missing' becomes 'absent' (similar in meaning).
'having' is an insertion indicator.
'can inside' becomes 'tin' (synonyms. I am not sure about the 'inside' bit.).
'absent' placed around 'tin' is 'ABSTINENT'.

Can you help me to learn more?

(Other definitions for abstinent that I've seen before include "Forsaking alcohol" , "Not indulging appetite for food or drink" , "Avoiding alcohol" , "Restrained" , "Refusing alcohol" .)

I've seen this clue in The Telegraph.

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