How to split strings across multiple lines in CMake?

Question

I usually have a policy in my project, to never create lines in text files that exceed a line length of 80, so they are easily editable in all kinds of editors (you know the

Answer 1

Update for CMake 3.0 and newer :

line continuation is possible with \. see cmake-3.0-doc

message("\
This is the first line of a quoted argument. \
In fact it is the only line but since it is long \
the source code uses line continuation.\
")

Availability of CMake versions:

Debian Wheezy (2013): 2.8.9
Debian Wheezy-backports: 2.8.11
Debian Jessy (2015): 3.0.2
Ubuntu 14.04 (LTS): 2.8.12
Ubuntu 15.04 : 3.0.2
Mac OSX : cmake-3 available through Homebrew, Macports and Fink
Windows: cmake-3 available through Chocolatey