From mboxrd@z Thu Jan  1 00:00:00 1970
From: tfb@tfeb.org (Tim Bradshaw)
Date: Thu, 8 Jun 2017 19:41:55 +0100
Subject: [TUHS] Array index history
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> On 7 Jun 2017, at 20:15, Arthur Krewat <krewat at kilonet.net> wrote:
> 
> In the days when memory and clock cycles were costly, an extra decrement or subtract was not something to be taken lightly :)

Indeed they weren't, and that's how we know that 1-based indexing doesn't require any overhead given a reasonably good compiler.  If you'd gone to people writing big CFD simulations in 1975 and told them that by using a version of FORTRAN which had 0-based arrays they could save any significant runtime at all then they would have changed to it without a thought.  But they didn't.