Question

I want a macro that I can use like this:

CREATE_URL(@"{SOME-TOKEN}/some/url/path");

The macro should then replace my token analogue to the following call:

NSString *initialURL = @"{SOME-TOKEN}/some/url/path";
[initialURL stringByReplacingOccurencesOfString:@"{SOME-TOKEN}" withString:@"http://server.com"]

So I have defined my macro like this, which does not work unfortunately:

#define CREATE_URL(url) [##url stringByReplacingOccurencesOfString:@"{SOME-TOKEN}" withString:@"http://server.com"];

I the two errors when using the macro:

Missing '[' at start of message send expression
Pasting formed '[@', an invalid preprocessing token

Answer 1

Why not this?

#define CREATE_URL(url) [url stringByReplacingOccurencesOfString:@"{SOME-TOKEN}" withString:@"http://server.com"]

It should work fine… why the ## and the ;?