A possible alternative to dot notation for record access

[amindfv at gmail.com]

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_clayden at 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). ...
> 
> 
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