On 2018-May-17, Tom Lane wrote: > Robert Haas <robertmh...@gmail.com> writes: > > Hang on, I can't be wrong (famous last words). If the negative > > indexes were 0-based, that would mean that the first element of the > > list was referenced by -0, which obviously can't be true, because 0 = > > -0. In other words, we can't be using 0-based indexing for both the > > positive and the negative values, because then 0 itself would be > > ambiguous. It's got to be that -1 is the first element of the *pds > > list, which means -- AFAICS, anyway -- that the way I phrased it is > > correct.
> Maybe what you need is a redesign. This convention seems impossibly > confusing and hence error-prone. What about using a separate bool to > indicate which list the index refers to? That was my impression I first came across this, FWIW, and I confess I didn't try hard enough to understand it fully. -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
