ESP8266 Community Forum

- Mon Sep 14, 2015 3:47 pm #29047 For a while now, I have been using the little known <R"=====( . . . . )====="> Macro to assign large blocks of data within my Arduino IDE Esp Sketches. This Macro is used in several Examples, and Discussed in several threads within this Forum. For example See: http://www.esp8266.com/viewtopic.php?p=27964#p27964

But where can I find the R Macro Documentation, via this Forum, or via Google, that describes it "proper" use or definition? And, Where/How is it implemented?

Thanks,
Eldon - WA0UWH

- Tue Sep 15, 2015 2:05 am #29064 This isn't a macro, it's just a part of the language (introduced in C++11 standard), known as raw string literal.

Raw string literals look like
R"token(text)token"

the sequence )token must be chosen such that it doesn't appear inside text. In the example you mentioned this token is five equals signs.

http://en.cppreference.com/w/cpp/langua ... ng_literal

- Tue Sep 15, 2015 1:30 pm #29095

This isn't a macro, it's just a part of the language (introduced in C++11 standard), known as raw string literal.

http://en.cppreference.com/w/cpp/langua ... ng_literal

THANKS, igrr,

That solves a BIG mystery for me.

Eldon - WA0UWH