Learning, on coming upon unconscious (7,3)

I believe the answer is:

finding out

'learning' is the definition.
('find out' can be a synonym of 'learn')

'on coming upon unconscious' is the wordplay.
'on' says to put letters next to each other.
'coming upon' becomes 'finding' ('find' can be a synonym of 'come upon').
'unconscious' becomes 'out' (similar in meaning).
'finding' put next to 'out' is 'FINDING OUT'.

I've seen this clue in the Evening Standard.

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