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Annotation of coherent/a/usr/man/ALL/_2323, revision 1.1

1.1     ! root        1: 
        !             2: 
        !             3: ##                    Preprocessing Operator                   ##
        !             4: 
        !             5: 
        !             6: 
        !             7: 
        !             8: Token-pasting operator
        !             9: 
        !            10: 
        !            11: The preprocessing operator ## can be used in both object-like and
        !            12: function-like  macros.   When  used  immediately  before  or  im-
        !            13: mediately after  an element in  the macro's replacement  list, ##
        !            14: joins  the corresponding  preprocessor token  with  its neighbor.
        !            15: This is sometimes called ``token pasting''.
        !            16: 
        !            17: As an example of token pasting, consider the macro:
        !            18: 
        !            19: 
        !            20:         #define printvar(number) printf("%s\n", variable ## number)
        !            21: 
        !            22: 
        !            23: When the preprocessor reads the following line
        !            24: 
        !            25: 
        !            26:         printvar(5);
        !            27: 
        !            28: 
        !            29: it substitutes the following code for it:
        !            30: 
        !            31: 
        !            32:         printf("%s\n", variable5);
        !            33: 
        !            34: 
        !            35: The  preprocessor throws  away all  white  space both  before and
        !            36: after the ##  operator.  This gives you an easy  way to print any
        !            37: one of a set of strings.
        !            38: 
        !            39: ## must not  be used as the first or  last entry in a replacement
        !            40: list.  All instances of  the ## operator are resolved before fur-
        !            41: ther macro replacement is performed.
        !            42: 
        !            43: For more information on object-like and function-like macros, see
        !            44: #define.
        !            45: 
        !            46: ***** See Also *****
        !            47: 
        !            48: #, #define, C preprocessor
        !            49: 
        !            50: ***** Notes *****
        !            51: 
        !            52: Token pasting  has been performed by separating  the tokens to be
        !            53: pasted with an empty comment, but this is no longer necessary.
        !            54: 
        !            55: The order of evaluation of multiple ## operators is unspecified.
        !            56: 
        !            57: 
        !            58: 
        !            59: 
        !            60: 
        !            61: 
        !            62: 
        !            63: 
        !            64: COHERENT Lexicon                                           Page 1
        !            65: 
        !            66: 

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