```Chinna Karuppan wrote:
> Hi,
> I am trying to under this operator |=.Has anybody got some documentation
> / online link to explain this....
>
>
>
>
> THnks
> Chinna

The number 10 written in binary format is:

8's   4's   2's   1's
---   ---   ---   ---
1     0     1     0

The number 11 written in binary format is:

8's   4's   2's   1's
---   ---   ---   ---
1     0     1     1

Assume 1 is equal to true and 0 is equal to false.  Now OR each column
together:

1  0  1  0
1  0  1  1  OR
----------
<--result?

In the first column(the leftmost column) you have (true OR true), which
is true, i.e you write 1 for the result:

1  0  1  0
1  0  1  1  OR
----------
1          <--result?

In the second column, you have (false OR false), which is false, i.e you
write a 0 for the result:

1  0  1  0
1  0  1  1  OR
----------
1  0       <--result?

In the third column, you have (true OR true), which is true:

1  0  1  0
1  0  1  1  OR
----------
1  0  1    <--result?

In the last column, you have (false OR true) which is true:

1  0  1  0
1  0  1  1  OR
----------
1  0  1  1 <--result?

What number is that?

8's   4's   2's   1's
---   ---   ---   ---
1     0     1     1

1x8 + 0x4 + 1x2 + 1x1 = 11.  So 10 | 11 is equal to 11.

The syntax a |= b is similar to the syntax a += 1.  a += 1 is equivalent
to a = a + 1.  So a |= b is equivalent to a = a | b.  From the above you
should now know how to OR two numbers together: convert the numbers to
binary format and then OR the columns together.

--
Posted via http://www.ruby-forum.com/.

```