CONST arithmetic

From: Campbell, Robert D (UK Edinburgh) <"Campbell,>
Date: Thu, 02 Dec 2004 11:07:42 +0000

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I have some code:

CONST
  arrayLen = 5;
  arrayMax = arrayLen - 1;

VAR
  xyx : REAL;

BEGIN
  xyz := 100. / arrayMax;


Fine.
But for a simple test case I set arraylen = 1.
I get a compiler error 'division by zero'.

This is not an error; my algorithm will work fine with
xyz = INF.

Even if I add

  IF arraylen > 1 THEN xyz := 100. / arrayMax END

I still get a compiler error.

Is this a restriction in the language, or the compiler, or ...?

I thought that the compiler removed 'dead' code of the form:

IF FALSE THEN ... END anyway.

Robert

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Received on Thu Dec 02 2004 - 12:07:42 UTC