From: james@...
Date: 2002-04-14T01:12:39+09:00
Subject: RE: not vs !, and vs &&



> -----Original Message-----
> From: Guy N. Hurst [mailto:gnhurst@hurstlinks.com]
> 
<snip />

> Meanwhile, 'true' is an expression and '!true' is an expression, but
> combining them with 'and' forms a statement.
> (combining them with '&&' would have formed another expression directly)

So, 'and' and '&&' are *not* synonyms that differ only in precedence?
(Likewise for '!' and 'not' )



> 
> You must enclose a ruby statement in parentheses to form a ruby 
> expression.
> 
> puts( (true and !true) )
> puts( (not true) )
> 
> This demonstrates the slight difference between a ruby 'statement' 
> and a ruby 'expression'. Statements must be enclosed in parentheses
> to form an expression, which is required for using them as an argument.


In this example:

#-----------------------------------
def nt
  puts "Inside nt"
  not true
end

put nt     # Prints 'Inside nt', then 'false'
#-----------------------------------


Why does the last line of the method nt act as an expression?


Thanks,


James

> 
> 
> Guy N. Hurst
>