Hi Eric,
>Speaking of datatypes, here's a puzzle! (If you're sick of puzzles, think
>of it as a conundrum ;-)
>
>Why does this happen?
>
>>> array2: func third :array second :array
>>> array2 8
>** Script Error: array2 expected size argument of type: datatype datatype.
>** Where: array2 8
I don't really think this qualifies as a puzzle, does it? A similar
phenomenon was discussed in June 1999, first reported by Gisle. Gabriele
pointed out at the time (We are speaking REBOL version 2.0 or 2.1):
>>>>>>> Gabriele:
>> print mold :make_average_obj
func [/local data][
data: copy []
sum: func [numbers] [either tail? numbers [0] [(sum next numbers) + first
numbers]]
make object! [
add_integer: func [value [integer!]] [append data value true]
average: func [] [(sum data) / (length? data)]
]
]
>> print mold a
make object! [
add_integer: func [value [integer!]][append data value true]
average: func [][(sum data) / (length? data)]
]
>> b: make_average_obj
>> print mold :make_average_obj
func [/local data][
data: copy []
sum: func [numbers] [either tail? numbers [0] [(sum next numbers) + first
numbers]]
make object! [
add_integer: func [value [datatype!]] [append data value true]
average: func [] [(sum data) / (length? data)]
]
]
>> print mold b
make object! [
add_integer: func [value [datatype!]][append data value true]
average: func [][(sum data) / (length? data)]
]
>> print mold a
make object! [
add_integer: func [value [datatype!]][append data value true]
average: func [][(sum data) / (length? data)]
]
integer! becomes datatype! after the second call to the function.
I havo no idea about the reason, but it seems like the block
[integer!] is somehow reduced...
<<<<<<<<<<<<<<<<< End Gabriele
This appears to have been fixed with respect to objects. The current
version of REBOL acts as expected:
>> print mold :make_average_object
func [/local data][
data: copy []
sum: func [numbers] [either tail? numbers [0] [(sum next numbers) + first
numbers]]
make object! [
add_integer: func [value [integer!]] [append data value true]
average: func [] [(sum data) / (length? data)]
]
]
>> print mold :a
make object! [
add_integer: func [value [integer!]][append data value true]
average: func [][(sum data) / (length? data)]
]
>> print mold :b
make object! [
add_integer: func [value [integer!]][append data value true]
average: func [][(sum data) / (length? data)]
]
Note that in Gabriele's example above, print mold :b contained the line:
add_integer: func [value [datatype!]][append data value true]
whereas in version 2.2 the line is now:
add_integer: func [value [integer!]][append data value true]
The type specifier integer! has been preserved and was not replaced by
[datatype!].
Apparently, REBOL continues to replace integer! by datatype! when make
function! has been evaluated. In your example, REBOL returns:
>> array2: func third :array second :array
>> print mold :array2
func [
"Makes and initializes a series of a given size."
size [datatype! datatype!] "Size or block of sizes for each dimension"
/initial "Specify an initial value for all elements"
value "Initial value"
/local block rest
][
if not initial [value: none]
rest: none
if block? size [
rest: next size
if tail? rest [rest: none]
size: first size
if not integer? size [make error! "Integer size required"]
]
block: make block! size
either not rest [insert/dup block value size
] [
loop size [
block: insert/only block array/initial rest value
]
]
head block
]
Note the line:
size [datatype! datatype!] "Size or block of sizes for each dimension"
I think it's a bug Eric, which is why I'm not sure it really qualfies as a
"puzzle".
;- Elan >> [: - )]
