natn

#natn

##Syntax

(a) nat1 % 1-byte natural number (b) nat2 % 2-byte natural number (c) nat4 % 4-byte natural number

##Description The nat_n_ (n-byte natural number) types are machine-dependent types that occupy a specified number of bytes. By contrast, the nat type is in principle a machine-independent and mathematical type (it overflows, however, when the value is too large or small, that is, when the value does not fit into 4 bytes).

##Example

    var counter1 : nat1     % Range is 0 .. 255
    var counter2 : nat2     % Range is 0 .. 65536
    var counter4 : nat4     % Range is 0 .. 4294967295

##Details In Turing, the range of the nat is 0 to 4294967294, which means that the nat4 type allows one more value, 4294967295. This extra value is used in nat to represent the state of being uninitialized. The nat_n_ types allow use of all possible values that fit into n bytes and thereby eliminates checking for initialization.

The nat_n_ types are like the C language types short unsigned, unsigned, and long unsigned, except that the number of bytes occupied by the C types depends on the particular C compiler.

##See also the int.htmln types which are n byte integer values. See also nat.html and int.html.