Have pee whilst swimming (5,4)

I believe the answer is:

sleep with

'have' is the definition.
('sleep with' can be a synonym of 'have')

'pee whilst swimming' is the wordplay.
'swimming' is an anagram indicator.
'pee'+'whilst'='peewhilst'
'peewhilst' anagrammed gives 'SLEEP WITH'.

I've seen this clue in The Independent.

Want a hint initially instead of a full solution? Install my app