On 2008-04-17, Maury Pepper <mpepper_scram_spam@[EMAIL PROTECTED]
> wrote:
>
> "Duke Normandin" <dukeofperl@[EMAIL PROTECTED]
> wrote in message
> news:0OzNj.681$n63.637@[EMAIL PROTECTED]
>>
>> Then how does one differentiate between a local and global variables;
>> and local and global variable arrays? I see that global arrays have the
>> ^ prefix. Do global (scalar) variables have the ^ prefix as well. If
>> yes, how can I tell what I'm dealing with -- a global variable or a
>> global array?
>> --
>> Duke Normandin
>
>
> Here is a definition from The Annotated M[UMPS] Standard
> (http://71.174.62.16/Demo/AnnoStd)
> 4.2 array: M arrays, unlike those of most other computer languages, are
> trees of unlimited depth and breadth. Every node may optionally contain
a
> value and may also have zero or more descendant nodes. The name of a
> subscripted variable refers to the root, and the nth subscript refers to
a
> node on the nth level. Arrays vary in size as their nodes are set and
> killed. See scalar, subscript.
>
> Since there are no variable declarations, one could simply say that an
array
> is a variable with subscripts. Note that the definition says that arrays
are
> trees. So, which are they -- arrays or trees? Well, they are actually
trees
> which are referenced as if they were arrays, but since they are trees,
they
> behave differently than arrays.
I'm going to have to study the above a bit more ;))
> You can tell if a variable is subscripted by using the $DEFINE
(abbreviated
> $D) function. For example, if $D(X) returns 1, then variable X has a
defined
> value but no pointer to a descendant.node -- ie, it is currently a
scalar.
Thanks for the pointer! However are you implying that a scaler variable
can be
morphed into an array?
> You asked about MUMPS versions. If you want to climb inside and play
with
> the source code, MUMPS V1 is fine, and it is pretty close to standard
Mumps.
^^^^^^^^
Do you mean Ray Newman's incarnation of Mumps?
> GT.M is much closer to a full standard Mumps and is an industrial
strength
> commercial product and is sup****ted. It just happens to be open source
on
> certain platforms. Kevin OKane's Mumps is far from standard but has many
> interesting features not found in generic Mumps. Cache
Close enough I guess. Have to keep it in mind.
--
Duke Normandin
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