Preprocessing ##

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From	Hans-Peter Diettrich <DrDiettrich1@netscape.net>
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Subject	Preprocessing ##
Date	Sat, 13 May 2017 08:49:36 +0200
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How is the C preprocessor assumed to handle the ## concatenation operator?

In the Windows headers I found macros like
   #define foo(x) bar(##baz(x))
where an expansion into ... (baz ... doesn't make sense, because "(baz"
is not a valid preprocessor token. Can somebody explain the meaning and
handling of such constructs?

DoDi [I would guess that some macro between ( and ## expanded to
nothing.  Or it could just be one of those text editing errors. -John]

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Preprocessing ## Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2017-05-13 08:49 +0200
  Re: Preprocessing ## Hans-Peter Diettrich <DrDiettrich1@netscape.net> - 2017-05-15 11:28 +0200
  Re: Preprocessing ## Kaz Kylheku <686-678-9105@kylheku.com> - 2017-05-15 13:41 +0000
  Re: Preprocessing ## George Neuner <gneuner2@comcast.net> - 2017-05-15 11:31 -0400
    Re: Preprocessing ## Hans-Peter Diettrich <DrDiettrich1@aol.com.dmarc.email> - 2017-06-02 08:04 +0200

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