World: r3wp

>> if first find [false true] 'false [print "false is the first element"]
false is the first element

>> probe 1 = 0
false
== false
>> probe first find [false true] 'false
false
== false

>> pick [true "false is the element"] false
== "false is the element"

>> type? probe 1 = 0
false
== logic!
>> type?  probe first find [false true] 'false
false
== word!

Fork the false is being returned because it is the last value.

>> (1 = 0) = (first find [false true] 'false)
== false

in [false true], both are word! values, not logic!. If you want logic! 
values : logic! = first find reduce [false true] false

>> (1 = 0) = (first find reduce [false true] false)
== true

A ha

Is there a version of probe that prints the type also?

Not by default, but here's one : probe*: func [value][probe :value 
probe type? :value :value]

Dockimbel: very useful!

>> if 'hedgehog [print "hedgehog"]
hedgehog

Oh my.  Well, I think I'd rather define a "safe" if that only accepts 
true/false if there isn't such a thing

In REBOL everything is TRUE except false and none! values.

Btw, " favorite_fruit/set-value 'banana " doesn't look very rebolish 
to me...IMHO, REBOL way would be more like : " set-enum favorite_fruit 
'banana ". When you MAKE an object! in REBOL, all its functions are 
duplicated, so keeping the functions inside an object! and using 
it as in a class/instances model ends up eating a lot of memory. 
That's why the more "rebolish" way, where the code is out of the 
objects, is the way to go if you deal with a lot of instances (which 
might be the case for a "class" like enum!).  Remember that REBOL 
objects are prototype-based, meaning that they are created by cloning, 
not by instantiating a class. R3 will maybe bring us true class! 
datatype or at least a clean way to implement it by ourselves.

To check, if false is the first element:


>> if head? find [false true] 'false [print "false is the first element"]
false is the first element

>> if head? find [true false] 'false [print "false is the first element"]
== none

Geomol: good point... that wasn't what I was doing, the quote should 
have been "false is in the list"  :)

Dockimbel: That's quite good to know, thank you, I will make that 
change.

It was a quick ping-pong up there, so I'm not sure, if you know the 
answer, but to find false in a series:

>> if find [false true] 'false [print "false is in the list"]
false is in the list

And you know, this isn't the value FALSE, it's just words.

To check for the logic! value FALSE, you have to reduce the block:


>> if find reduce [false true] false [print "The logic! value false 
is in the series"]
The logic! value false is in the series

>> if find reduce ['false true] false [print "The logic! value false 
is in the series"]
== none

>> if ( reduce first find [false true] 'false ) [print "false is 
in the list"]
false is in the list

I'm looking for how to make first find [false true] 'false NOT print 
false is in the list

As per my usual question method, if y is ( reduce first find [false 
true] 'false )... what is f(y) to make that happen :)

because FALSE there is a word!, not  logic!.

>> first find [false true] 'false
== false
>> type? reduce first find [false true] 'false
== word!

That much I get, I just thought that reduce turned false-as-word 
into false-as-logic and it does not

Yes, it's still a word! and not a logic!, even if you reduce it.

So what turns it into a logic, if not reduce?

do

reduce the block instead

>> if ( do first find [false true] 'false ) [print "false is in the 
list"]
== none

looks like R3 does not exhibit that behavior. it's reduced to logic!

Ok, great, that's the case I was worried about then...

Or LOAD:
>> load to string! 'false
== false

I'm confused as to why reduce, which seems to perform other evaluations, 
would not (in R2) turn false into a logic!... Henrik, you are saying 
it does?

Fork, Rebol 3 does, so this may be an inconsistency in Rebol 2.

It's often works, if you turn stuff into a string and then load that. 
Other ways to turn stuff into strings:

>> load mold 'false
== false
>> load form 'false
== false

*It* often works ...

Not quite;    reduce 'false  is a word,  reduces as a word!     reduce 
[false]   reduces the block, evaluating false to the logic! false. 
  It's fun stuff.   ;)    mold/all  can be your friend exploring 
the ins and outs of evaluated values.

oops! :D

Sorry John; responding to Forks confused post not yours.   I always 
trust Geomol advice  :)

I got confused too. :)) REBOL is funny to play with!

>> type? load form 'false
== word!
>> type? load mold 'false
== word!

In R2, REDUCE main purpose is to reduce block! values. For general 
evaluation use DO.

btiffin, I make mistakes too! :-)

Yeah any word! reduced is still the word!

sorry:

>> type? false
== logic!
>> type? reduce false
== logic!

R2 and R3 behave identically here.

Henrik, yes, but
>> type? reduce 'false
== word!

Is that the same in R3?

It seems like reduce is a core notion, and it would be nice to see 
a list mapping what conversions it performs.  Changing that between 
R2 and R3 seems rather... fundamental?

Fork;   There are also "lexical forms" for all these values.   #[false] 
 is loaded by REBOL as the logic! value false.  No need to evaluate 
in that case.

John; yes.