From: Dave Thomas <Dave@...>
Date: 2002-01-24T11:45:01+09:00
Subject: Re: a can be true and false

moontoeki@aol.com (Sung Moon) writes:

> a can be true and false at the same time
> 
> a = ""
> if a != true; p "a is false" ; end
> if a; p "a is true" ; end
> 
> this produces:
> 
> a is false
> a is true
> 
> It means a can be true and false at the same time.
> Am I right?

No.

'a' is neither true nor false. 'a' is a String.

In boolean contexts (such as in an 'if' statement), anything apart
from 'false' and 'nil' makes the test succeed.

So:  "a" != true    #=>  true  (a is a string)
     if a           #=> test succeeds (a is not false of nil)


Is just the same as

     if (99) ....
     if (99 == TRUE) ...

in C



Dave