US /ˈhævɪŋ ə weɪl əv ə taɪm/
・UK /ˈhævɪŋ ə weɪl əv ə taɪm/
If you're really enjoying yourself, perhaps at work or at the funfair or at a party or dinner, then you could say that "I'm having a 'whale of a time'."
I'm having a whale of a time.
It's just having a whale of a time.