Tireless debating if ale is drunk (13)

I believe the answer is:

indefatigable

'tireless' is the definition.
(synonyms)

'debating if ale is drunk' is the wordplay.
'is drunk' indicates an anagram.
'debating'+'if'+'ale'='debatingifale'
'debatingifale' is an anagram of 'INDEFATIGABLE'.

(Other definitions for indefatigable that I've seen before include "Unflagging" , "Unremitting" , "Tireless" , "with no end of energy" , "Persistent" .)

I've seen this clue in The Telegraph.

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