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   <H1>[99s-extend] Cowboy: Maps instead of records for context variables</H1>
    <B>Lo&#239;c Hoguin</B> 
    <A HREF="mailto:extend%40lists.ninenines.eu?Subject=Re%3A%20%5B99s-extend%5D%20Cowboy%3A%20Maps%20instead%20of%20records%20for%20context%0A%20variables&In-Reply-To=%3C5626401F.9050907%40ninenines.eu%3E"
       TITLE="[99s-extend] Cowboy: Maps instead of records for context variables">essen at ninenines.eu
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    <I>Tue Oct 20 15:22:39 CEST 2015</I>
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<PRE>On 10/20/2015 03:19 PM, Ivan Uemlianin wrote:
&gt;<i> Dear All
</I>&gt;<i>
</I>&gt;<i> Would there be any reason against using a map instead of a record for
</I>&gt;<i> the context variable in a Cowboy REST resource?
</I>&gt;<i>
</I>&gt;<i> Quite often I have a few resources doing very similar things in their
</I>&gt;<i> callbacks, and I'd like to abstract out the similarities into a module -
</I>&gt;<i> but I don't want to share a record between modules.
</I>&gt;<i>
</I>&gt;<i> Maps seem to be a good fit, and I can't think of any downside
</I>&gt;<i> (performance hit should be tiny).
</I>&gt;<i>
</I>&gt;<i> Can anyone give me reasons to stick with records?
</I>
The only reason to use records is to keep typespecs information to 
improve Dialyzer's error reporting.

Personally I have no problems going with just maps for all kinds of 
states, even if they are in the same module. This is partly because I 
rely a lot more on tests than on Dialyzer to tell me my program is wrong.

Cheers,

-- 
Lo&#239;c Hoguin
<A HREF="http://ninenines.eu">http://ninenines.eu</A>
Author of The Erlanger Playbook,
A book about software development using Erlang
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