something like this came up on irc the other day. this is a good
opportunity for someone to write some macros that allow you to
specify a validator function for structs similar to refs and agents.
On Sat, Mar 28, 2009 at 2:20 PM, mikel <mev...@mac.com> wrote:
>
>
>
> On Mar 28, 4:05 pm, billh04 <h...@tulane.edu> wrote:
>> I am using keywords as constants in my clojure programs, but I am
>> worried about misspelling them. For example, I am writing a game and I
>> am using the keywords :north and :south to indicate objects that
>> belong to the north player or the south player. With this, I can
>> define how to create the pieces for the players:
>>
>> (defn createPiece [id player] {:tag ::piece, :id id, :player
>> player})
>>
>> where player can take the values :north or :south. I have many other
>> such constants in the program.
>>
>> I have been thinking of doing the following to catch misspellings:
>>
>> (def -north- :north)
>> (def -south- :south)
>>
>> and then using these two definitions as follows:
>>
>> (def northPiece1 (createPiece 1 -north-))
>>
>> rather than doing this:
>>
>> (def northPiece1 (createPiece 1 :north))
>>
>> But, before I make these changes, I wondered if anyone else has run
>> into this problem, and if it is worth it to consider an option to be
>> able to declare the known constant keywords that will be used in the
>> program and then treat the undeclared keywords as warnings?
>>
>> Another option would to be able to get a cross-reference of all
>> keywords in the clj files within a folder (and subfolders) that shows
>> where they are declared and used (like was done for Cobol programs in
>> the 1970's).
>
> Another option you might consider is defining functions that sanity-
> check your keys and values, so you can say, for example
>
> (defn createPiece [id player]
> (with-allowed-keys
> [:player :tag :id]
> (with-allowed-values
> {:player [:north :south]}
> {:tag ::piece,
> :id id,
> :player player})))
>
>
> >
>
--
And what is good, Phaedrus,
And what is not good—
Need we ask anyone to tell us these things?
--~--~---------~--~----~------------~-------~--~----~
You received this message because you are subscribed to the Google Groups
"Clojure" group.
To post to this group, send email to clojure@googlegroups.com
To unsubscribe from this group, send email to
clojure+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/clojure?hl=en
-~----------~----~----~----~------~----~------~--~---
