Re: How to improve performance when reading text files?

szabolcs.szucs wrote:
Append is the key. Because of you collecting lines into a list which
is a simply linked one
(afaik) when appending to the end, you have to iterate over the list
every time. This makes the solution O(n^2).. A somewhat better
solution is to (cons line retval) and return (reverse retval) which
makes stuff linear (O(n)), although consider using arrays.
True.
Even better (faster) is returning (nreverse retval).
.

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