17.6.1.0170 -TRAILING dash-trailing STRING
( c-addr u1 -- c-addr u2 )
If u1 is greater than zero, u2 is equal to u1 less the number of spaces at the end of the character string specified by c-addr u1. If u1 is zero or the entire string consists of spaces, u2 is zero.
Testing:
T{ : s8 S" abc " ; -> }T
T{ : s9 S" " ; -> }T
T{ : s10 S" a " ; -> }T
T{ : s9 S" " ; -> }T
T{ : s10 S" a " ; -> }T
T{ s1 -TRAILING -> s1 }T \ "abcdefghijklmnopqrstuvwxyz"
T{ s8 -TRAILING -> s8 2 - }T \ "abc "
T{ s7 -TRAILING -> s7 }T \ " "
T{ s9 -TRAILING -> s9 DROP 0 }T \ " "
T{ s10 -TRAILING -> s10 1- }T \ " a "