As long as we're bikeshedding... Possibly '#' is unused syntax -- Erlang uses it for its records too, so we wouldn't be pulling it out of thin air. E.g. "person#firstName"
Tom El Jun 30, 2013, a las 22:59, AntC <anthony_clay...@clear.net.nz> escribió: >> Carter Schonwald <carter.schonwald <at> gmail.com> writes: >> >> indeed, this relates / augments record puns syntax already in > GHC http://www.haskell.org/ghc/docs/latest/html/users_guide/syntax- > extns.html#record-puns. > > Uh-oh. That documentation gives an example, and it exactly explains the > weird type-level error I got when I tried to use the proposed syntax > myself: > > Note that: > > * Record punning can also be used in an expression, writing, for > example, > > let a = 1 in C {a} -- !!! > > instead of > > let a = 1 in C {a = a} > > The expansion is purely syntactic, so the expanded right-hand side > expression refers to the nearest enclosing variable that is spelled the > same as the field name. > > IOW the proposal _does_ conflict with existing syntax. (And I guess I can > see a use for the example. Note that outside of that let binding, `a` > would be a field selector function generated from the data decl in which > field `a` appears -- that's the weirdity I got.) > > I suppose the existing syntax has a data constructor in front of the > braces, whereas the proposal wants a term. But of course a data > constructor is a term. > > So the proposal would be a breaking change. Rats! Is anybody using that > feature? > >> >> On Sun, Jun 30, 2013 at 2:59 AM, Judah Jacobson <judah.jacobson <at> > gmail.com> wrote: >> >> Unlike dot notation, this is unambiguous and doesn't conflict with any > existing syntax (AFAIK). ... > > > _______________________________________________ > Glasgow-haskell-users mailing list > Glasgow-haskell-users@haskell.org > http://www.haskell.org/mailman/listinfo/glasgow-haskell-users _______________________________________________ Glasgow-haskell-users mailing list Glasgow-haskell-users@haskell.org http://www.haskell.org/mailman/listinfo/glasgow-haskell-users