c preprocessor - What's the meaning of ## in the define code in C++ -


this question has answer here:

#define declare_delete_ptr(type) \ void deleteptr_##type(string &operand) \ {\ }\

what's meaning of ## in macro definition in c++?

what's difference followed code?

#define make_strings(var) #var

it 1 #, former 2 #

it concatenates value pass through parameter type...

declare_delete_ptr(gremlin)

would expand to:

void deleteptr_gremlin(string &operand) { }

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