Changes between Version 18 and Version 19 of Records

Timestamp:

12/29/11 08:48:48 (17 months ago)

Author:

GregWeber

Comment:

namespacing - TDNR & module ideas

Records

@@ -51 +51 @@
 
  [http://code.google.com/p/frege/ Frege] takes this approach; see Sections 3.2 (primary expressions) and 4.2.1 (Algebraic Data type Declaration - Constructors with labeled fields) of the [http://code.google.com/p/frege/downloads/detail?name=Language-202.pdf Frege user manual].
+
 The module/record ambiguity is dealt with in Frege by preferring modules and requiring a module prefix for the record if there is ambiguity. So if your record named Record was inside a module named Record you would need `Record.Record.a`. I think for the most part programmers will structure their programs to avoid this situation.
 
- * '''Use the module name space mechanism'''; after all that's what it's for.  But putting each record definition in its own module is a bit heavyweight. So maybe we need local modules (just for name space control) and local import declarations.  Details are unclear. (This was proposed in 2008 in [http://www.haskell.org/pipermail/haskell-cafe/2008-August/046494.html this discussion] on the Haskell cafe mailing list and in #2551. - Yitz)
+Verbosity is solved in Frege by using the TDNR concept. In `data Record = Record {a::String};r = Record "A"; r.a` The final `r.a` resolves to `Record.a r`.
+
+ * '''Use the module name space mechanism'''; after all that's what it's for.  But putting each record definition in its own module is a bit heavyweight. So maybe we need local modules (just for name space control) and local import declarations.  Details are unclear. (This was proposed in 2008 in [http://www.haskell.org/pipermail/haskell-cafe/2008-August/046494.html this discussion] on the Haskell cafe mailing list and in #2551. - Yitz).
+
+Rather than strictly re-use modules it would make more sense to have a name-spacing construct that is shared between both records and modules - hopefully this would make implementation easier.
 
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