[REBOL] while statement problem Re:(4)
From: rebol:techscribe at: 3-Oct-2000 11:17
[joel--neely--fedex--com] wrote:
> The REAL root cause of your error message is that REBOL doesn't use
> operator precendence (as other programming languages do). Consecutive
> operators are evaluated left-to-right, meaning that your original:
>
> prime and test <= square-root number
>
> is evaluated with the same meaning as
>
> (prime and test) <= square-root number
>
> which would try to apply and to a boolean and a number (and then would
> try to apply <= between a boolean and a number, but we don't get that far).
> The first of these generates the show-stopping error, as in:
Correct.
BTW, REBOL does accept boolean operations on integers, tuples and issues.
(perhaps other datatypes?) But all values must be consistent and share the same
datatype. For instance:
>> 1 and 1
== 1
>> 1 and 0
== 0
But
>> 1 and true
** Script Error: Expected one of: integer! - not logic!.
** Where: 1 and true
Elan
