Calculations are done on expr, if given. Otherwise, the standard input is used.
Numbers can be entered in hexadecimal (0xbeef), decimal (1984), octal (007),
and binary (0b1001). All numerical operators (+, -, *, /, %), bit operators
(|, ^, &, ~, <<, >>), and logical operators (==, !=, <, >, <=, >=, !, &&, ||)
are supported.
WWW: http://cyth.net/~ray/moo/
PR: ports/111824
Submitted by: Steven Kreuzer <skreuzer at f2o.org>