As always, rebuilding Rome would take no end of time (8)

I believe the answer is:

evermore

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'would take no end of time' is the definition.
I can't tell whether this defines the answer.

'as always rebuilding rome' is the wordplay.
'as always' becomes 'ever' (I've seen this before).
'rebuilding' indicates an anagram.
'rome' is an anagram of 'more'.
'ever'+'more'='EVERMORE'

Can you help me to learn more?

(Other definitions for evermore that I've seen before include "unceasingly" , "For which, permanently" , "Eternally" , "Always, forever" , "(For) perpetuity" .)

I've seen this clue in the Evening Standard.

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