No, doing that will force a bunch of \n into the string, or whatever depending on your OS.
Two ways you can do it
%req = "xyz...";
%req = %req @"xyz...";
%req = %req @"xyz...";
or
%req1 = "xyz...";
%req2 = "xyz...";
%req3 = "xyz...";
%req = %req1 @ %req2 @ %req3;