How to constrain Arduino library

Projects Programming
1 
Hi , I want to constrain an exist library with addition constrain, code like this 
[code]
#ifdef Trans
typedef MAX3421e<P53, P18>		MAX3421E;		// trans
#elif BOARD_BLACK_WIDDOW
typedef MAX3421e<P6, P3>		MAX3421E;		// Black Widow
#elif defined(BOARD_TEENSY_PLUS_PLUS)
typedef MAX3421e<P9, P8>        MAX3421E;       // Teensy++ 2.0 & 1.0
#elif defined(BOARD_MEGA_ADK)
typedef MAX3421e<P53, P54>              MAX3421E;               // Arduino Mega ADK
#else
typedef MAX3421e<P10, P9>		MAX3421E;		// Official Arduinos (UNO, Duemilanove, Mega, 2560
#endif

It is UsbHost library,, The "Trans" is defined in the sketch, a files that is in sketch folder. I can't find a way to pass the "Trans" to the library ,,
, How to keep "Trans" defined in the different files, and locate in different folder , not in library folder,,[/code]

2

I would look to see where the other variants are defined and define your variant the same way.

3

A preprocessor macro (#define) defined in a sketch cannot be referenced in a library.

It is a known (and often complained about) failing of the Arduino system.

4

That is sad,,, thanks