[REBOL] Re: Re(3): 'parse-url - where defined?
From: larry:ecotope at: 31-Jan-2001 10:29
Hi Anton
> Thanks guys,
>
> I've got DocKimbel's help patch,
> and Bo's browse-system.r.
>
> I really do need to spend some time
> poking through the system object more.
Yes! Currently that is the only way to move to guru status.
> One question:
> Is everything contained in the system object?
Short answer: Yes. Actually SYSTEM also has another name REBOL, it is the
root of the rebol system.
> Are all objects in 'system ?
Yes, but only those which are built-in at startup appear in the system
hierarchy. Of course, you can add to or modify the hierarchy (exercise
caution):
>> system/user: make system/user [nick: "sneaky"]
>> help system/user
OBJECT: user
WORDS:
email -- (Type: email)
home -- (Type: none)
name -- (Type: none)
nick -- (Type: string)
words -- (Type: none)
SUB-OBJECTS:
(none)
FUNCTIONS:
(none)
>> system/user/nick
== "sneaky"
So we have actually redefined part of the REBOL system.
> All words and objects defined by me -
> do they end up in 'system somewhere?
Yes, but not in the system hierarchy (unless you put them there as above).
In one sense of your question, "everything" is in system/words. It is the
dictionary or symbol table for the current invocation. The expression
first system/words
gives a block of all words seen by the scanner whether defined or not, in
all contexts.
The expression
second/system/words gives the corresponding block of *globally* known values
(may be unset!). In other words, it only gives a value if the word has a
value in the global context.
A good example of using these is:
>>source help
To track what you have defined, put this in your user.r
antons-stuff: 0
Then at any point in a script or console session,
>>find first system/words 'antons-stuff
returns a list of all the words you have used and their values (in the
global context) are the corresponding entries in the block returned by
second system/words.
May the source be with you, young Jedi ;-)
Cheers
-Larry
PS Things are actually a little more complicated than indicated above, but
this will put you on the right track.
