Remove unwanted character from String concat macro

[kamlmish1978]

Hi
I have a macro to do concatenation as below

#define dd Cloud
#define ff _Storage
#define CCM_BRAND_CONCAT2(a,b) a##b

The output is "Cloud _Storage" . Somehow theres extra space that gets added. Is there a way to remove the unawanted characters

[kigar64551]

Pre-processor macros are very limited in what they can do.

And, generally, you don't need a special macro to "concatenate" string literals. You can simply do:

#define FOO "foo"
#define BAR "bar"
const char* mystr = FOO BAR;

...which will be expanded to:
const char* mystr = "foo" "bar"; // equivalent to: const char* mystr = "foobar";


If you actually want to concatenate arbitrary strings at runtime, then you should be using:
https://cplusplus.com/reference/cstring/strcat/
https://cplusplus.com/reference/cstring/strncat/

...or, even better, work with std::string objects right away! ;-)

________

Anyhow, if you have a macro like the following...
#define MY_CONCAT(a,b) a##b

...then MY_CONCAT(foo,bar) will be expanded to exactly foobar. That is not a string though!

________

Strings can be created via macros using the following syntax:
#define MAKE_STR(s) #s

With the above macro definition, MAKE_STR(foo) will be expanded to "foo".