Hi,

This was reported by a debian user. Please retain a CC to
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so that the Debian BTS has a copy of your input.

The manual says:
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  ifdef variable-name
   
     The ifdef form takes the name of a variable as its argument, not a reference to a variable. The value of that variable has a non-empty value, the text-if-true is effective; otherwise, the text-if-false, if any, is effective. Variables that have never been defined have an empty value. The text variable-name is expanded, so it could be a variable or function that expands to the name of a variable.
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The second sentence of the first paragraph has a grammar error, it looks like it should read "If the value of that variable..."
 Also, "The value has a ... value" seems awkward.

 Manoj