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From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.acm.org>
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Subject: Re: Using a string as a binary operator
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Date: 2008-10-15T17:23:46+00:00
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Adam Beneschan wrote:
> 
> If-elsif-elsif-elsif-elsif-elsif-else chain?  That's not very
> imaginative!  Why not:
> 
>     type Operator_Descriptor is record
>         Name      : access String;
>         Operation : access function (Left, Right : Integer)
>                              return Integer;
>     end record;

I detest anonymous types.

> Although it isn't always possible, I definitely prefer to set things
> up in an array or some sort of data structure when possible, rather
> than to rely on a 67-branch IF statement or even a CASE statement.

By the time you've written all the support functions and the scaffolding to 
handle both unary and binary operations, your code is at least as big as with 
the big if statement, and less clear. If you're allowing a client to define the 
operators and their actions, this would be the way to go, but for hard-coded 
choices, I prefer the if statement.

-- 
Jeff Carter
"Unix and C are the ultimate computer viruses."
Richard Gabriel
99