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Where do we use ## in C ? 1
- Thread starter olikara
- Start date
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1
- #2
Hi,
This is how it is explained in MS help.
Token-Pasting Operator
Operator ##
Syntax token##parameter
parameter##token
----------------------------------------------------------
The token-pasting operator is used only with macros.
If ## precedes or follows a formal parameter in the definition of a macro, the actual argument is concatenated with the token on the other side of the ## when the macro is expanded. For example,
#define printvar(x) printf("%d", var##x)
causes the statement
printvar(7);
to be expanded into
printf("%d",var7);
Pappy
This is how it is explained in MS help.
Token-Pasting Operator
Operator ##
Syntax token##parameter
parameter##token
----------------------------------------------------------
The token-pasting operator is used only with macros.
If ## precedes or follows a formal parameter in the definition of a macro, the actual argument is concatenated with the token on the other side of the ## when the macro is expanded. For example,
#define printvar(x) printf("%d", var##x)
causes the statement
printvar(7);
to be expanded into
printf("%d",var7);
Pappy
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