Math::String::Charset::Nested 1.27

Math::String::Charset::Nested is a charset for Math::String objects.

SYNOPSIS

use Math::String::Charset;

# construct a charset from bigram table, and an initial set (containing
# valid start-characters)
# Note: After an a, either an b, c or a can follow, in this order
# After an d only an a can follow
$bi = new Math::String::Charset ( {
start => a..d,
bi => {
a => [ b, c, a ],
b => [ c, b ],
c => [ a, c ],
d => [ a, ],
q => [ ], # q will be automatically in end
}
end => [ a, b, ],
} );
print $bi->length(); # a,b => 2 (cross of end and start)
print scalar $bi->class(2); # count of combinations with 2 letters
# will be 3+2+2+1 => 8