Like this compiler would start to entertain digression (5)
I believe the answer is:
aside
'digression' is the definition.
('aside' can be a synonym of 'digression')
'like this compiler would start to entertain' is the wordplay.
'like' becomes 'as'.
'this compiler' becomes 'i' (the person who is writing these clues).
'would' becomes 'd' (I've seen this in other clues).
'start to' says to take the initial letters.
The initial letter of 'entertain' is 'e'.
'as'+'i'+'d'+'e'='ASIDE'
(Other definitions for aside that I've seen before include "Actor's covert line" , "Actors comment to his audience" , "Quiet words spoken" , "(Turn) off main path" , "Actor's line directed solely to audience" .)