/* No escape */
#define MESSAGE1 "@var1@"

/* Escaped whole variable */
#define MESSAGE2 "\\@var1\\@"

/* Replace pairs of escapes before '@' or '\@' with escape characters
 * (note we have to double number of pairs due to C string escaping)
 */
#define MESSAGE3 "\\\\@var1@"

/* Pairs of escapes and then an escaped variable */
#define MESSAGE4 "\\\\\@var1\@"

/* We don't gobble \@ prefixing some text */
#define MESSAGE5 "\\\\@var1"

/* Check escape character outside variables
                  \  @    \@ */
#define MESSAGE6 "\\ @ \\\\@"

/* Catch any edge cases */

/* no substitution - not a variable */
#define MESSAGE7 "@var1"

/* Escaped variable followed by another variable */
#define MESSAGE8 "\\\\@var1@var2@"

/* Variable followed by another variable */
#define MESSAGE9 "@var1@var2@"

/* Variable followed by another variable and escaped */
#define MESSAGE10 "@var1@var2\\\\@"

/* Lots of substitutions in a row*/
#define MESSAGE11 "@var1@@var2@@var3@@var4@"

/* This should never happen in the real world, right? */
#define MESSAGE12 "@var1@var2\\\\@var3@var4\\\\@"