[REBOL] Re: Storing a logical condition
From: gedb01::yahoo at: 13-Oct-2003 21:45
Hi Tim,
--- Tim Johnson <[tim--johnsons-web--com]> wrote: >
> Hello rebols:
> I'd like to store a logical condition in a block to
> evaluate at a later time by 'if or 'either
> Example code:
> >> a: 1
> == 1
> >> b: [a = 0]
> == [a = 0]
> >> either b[print "b evaluates to 'true'"][print "b
> evaluates to 'false'"]
> b evaluates to 'true'
>
> What do I need to do so that my answer will be:
> b evaluates to 'false'
>
> thanks
> tim
All you have to do now is 'do b':
>> a: 1
== 1
>> b: [a = 0]
== [a = 0]
>> do b
== false
>> a: 0
== 0
>> do b
== true
You can use it in conditionals like this:
>> either do b [print "A is zero"][print ["A is " a]]
A is zero
>> a: 42
== 42
