The monad u: applies to several kinds of arguments:
Argument 
Result 
char 
same as 2&u: 
wchar 
copy of argument 
integers 
same as 4&u: 
The inverse of the monad u: is 3&u:


The dyad u: takes a scalar integer left argument
and applies to several kinds of right arguments.
Left 
Result 

Right 
1  char  
char   as is 
wchar   highorder 8 bits discarded 

2  wchar  
char   highorder 8 bits are 0 
wchar   as is 

3  integers  
char or wchar 
4  wchar  
integers in the range 65536 to 65535 
5  char  
wchar in the range 0 to 255 
6  wchar  
pairs of chars are converted to wchars 
7  char or wchar  
U8   converted to wchar 
ASCII   as is 
wchar   if all values <128, convert to ASCII, otherwise as is 
an empty right argument produces an empty char result

8  U8  
wchar   converted to U8 
char   as is 
an empty right argument produces an empty char result

1&u: and 2&u:
, 3&u: and 4&u:
, and 7&u: and 8&u:
are inverse pairs.
