A digit to file at last (3)

I believe the answer is:

toe

'a digit' is the definition.
(digit on a foot)

'to file at last' is the wordplay.
'at last' suggests the final letters.
The last letter of 'file' is 'e'.
'to'+'e'='TOE'

(Other definitions for toe that I've seen before include "Digit on foot" , "Lower tip of something" , "Small member" , "compliantly put on line" , "Foot extremity." .)

I've seen this clue in the Evening Standard.

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