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MathGroup Archive 2009

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Head logic

  • To: mathgroup at smc.vnet.net
  • Subject: [mg97033] Head logic
  • From: carlos at colorado.edu
  • Date: Tue, 3 Mar 2009 05:55:49 -0500 (EST)

Entering

   ClearAll[r];
   Head[r]
   Head[r]!=Symbol
   Head[r]==Symbol

give Symbol, False and True as expected. But

   Head[r]==Integer

evaluates to Symbol==Integer. Why not False?
Head[r] is certainly not Integer. Likewise

  r=4;
  Head[r]==Integer
  Head[r]!=Symbol
  Head[r]==Symbol

give True (correct) but  Integer!=Symbol and Integer==Symbol.
Why not True and False?


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