As far as I understand, record syntax and data accessor only give access to the data, they don't provide alternate views / interpretations of the data, something that Active Patterns or view patterns in Haskell do? On Fri, Jan 16, 2009 at 4:27 PM, Henning Thielemann < lemm...@henning-thielemann.de> wrote:
> > On Fri, 16 Jan 2009, John Van Enk wrote: > > 2009/1/16 Peter Verswyvelen <bugf...@gmail.com> >> >> [...] >>> >>> After a while you decide that you need to change the Bla data type, maybe >>> give Dog more fields, maybe completely redesign it, maybe not exposing >>> it, >>> but you want to keep existing code backwards compatible. With F# you can >>> write Active Patterns for the old Dog and Cat constructors, so all >>> existing >>> code remains compatible. At least that is the way I understand it, but I >>> have not actually worked yet with Active Patterns, will do so soon :) >>> >>> You get something similar with the record syntax (though, probably still >> not >> quite as powerful as the active patterns): >> > > ... or use data-accessor package. >
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