This won't work.
I tried sending tranthidung 0-1 and 1-.0 merits and it didn't work showing invalid amount error.
It's not ignoring all other characters if they are written between two or more numbers.
It seems theymos only excluded - when he fixed that bug in 2018. For other characters, they all work. My guess only because I can not test all of them as it will force me to send out many merit.