func MyCustomLoggerHandler(ctx *macaron.Context) {
logger := &MyCustomLogger{ctx.Req}
ctx.Map(logger) // mapped as *MyCustomLogger
m.Get("/", MyCustomLoggerHandler, func(logger *MyCustomLogger) {
// Operations with logger.
m.Get("/panic", func(logger *MyCustomLogger) {
// This will panic because no logger service maps to this request.