World: r3wp

Perspectives of a newbie! By Steve Thornton (SteveT)


Hi! everyone, as someone brand new to REBOL I've been asked to log 
a journal
describing my experiences using REBOL. 


I think the first thing to get out of the way is to tell you where 
I'm coming

to REBOL from. I've programmed on and off for over twenty years starting 
with

Clipper 5 (dBaseII), Visual Basic (Access), C# (SQL Server), Java(NetBeans 
+

JavaDB). I've worked in a variety contract/freelance work. I earn 
approx half 

my income form 'Thornton Software' and I work for Iris Software Group 
- 

as a training consultant (training accountants :-\ someone has to 
do it!)


I can hear some of you saying 'Ahh! he's an IDE wimp - real men/women 
code

from scratch'. It was strange - every language I've used had an IDE 
and I

was a bit put off having to go find myself an editor. Until something 
better

find's me I'm using the freebie 'CREdit' as recommended by Sunanda. 


The easiest way to edit/test the scripts is to open an explorer window 
at

the side of the CREdit window showing my scripts folder. I can then 
drag a .r 

file onto the CEdit screen and it opens it. To run the script I double-click
it in the explorer window.


The help and documentation available is better than I have previously

experienced. Some of the components I've been wow'ed by so far is 
Henriks

List-View and RebDb from Dobeash. I've looked at RebGUI and for the 
time being 

I would prefer not to use anything on top of VID, I need to learn 
pure VID before
using anything else.


REBOL Cookbook of examples is a useful place to start. Some more 
form oriented 

examples would be cool. Example 014 - 'Open two windows'  and Example 
10 - 'Simple text
form window' are both useful


The Event Handling guide is a good resource for programmers moving 
from Visual
Studio etc..


That's more than enough to be going on with, next time I'll cover 
my experiences 
with VID, FACES and handling Events.

Bye for now.
Steve Thornton

Thanks, Gabriele!

Good post Steve. I was an "IDE wimp" myself, having from from QuickBASIC, 
PDS, VB, and others. I never thought I would use a language without 
one, but REBOL is just that good. :-)

And when we finally do have higher level tools for building things 
with REBOL, it will be that much better.

Excellent summary Steve. Don't be shy about mentioning things that 
tripped you up or could have been explained / presented better ... 
this is one of the few communities that takes constructive criticism 
very well! ;)

Some of my old Java buddies always said that an IDE can get in the 
way of what the programme is supposed to be doing, I'm beggining 
to see what they meant.

Thanks Ashley, I'm amazed at how generous people are here. (Not blowing 
any smoke ther ;-)  But some of the Microsoft communities are very 
elitist. Even though I'm a very experienced VS developer I hate how 
they talk to some of the newbies.

I think my journal (blog) whatever may be useful because I can see 
a lot of Visual Studio developers moving to REBOL - especially when 
3 is fully fledged. Things like VID3 / SVG Graphics etc will be very 
powerful. If I had one comment so far it would be not to rest on 
your laurels as far as the built in widgets are concerned - Everything 
is moveing to a 'RICHER' experience for the user, we can't get away 
with grey-old programmes anymore. The biggest internet buzzword of 
late is RIA  (Rich Internet Applications). With broadband, users 
expect the client side to be richer. REBOLS simplicity and size mean 
it should get miles ahead of the competition. Bill Gates's keynote 
speach recently covered this particular subject.

Perspectives of a newbie! By Steve Thornton (SteveT) 


In your first steps in using REBOL (If your like me) you'll go and 
have a look

at other peoples scripts - luckily the REBOL Viewtop is full of them. 


One thing that stumped me to begin with was that each developer differed

slightly in how they setup their 'Layout' or 'Views' this is because 
there is

a degree of flexibility that covers different situations. You can 
call a view 

and a layout all in one go, or you can make a layout seperately and 
then call 

it when executing the view. While I quickly understood this, I like 
to follow 

'best practice' when creating the initial framework of my application.


It would be a great help if a diagram was available showing where 
to place 

things. For example I went wrong by trying to place view options/effects 

inside the layout structure, When you look at some of the one/two 
line examples
it looks as if you can do that.

Steve

Steve, another insightful post.  I'm far from an expert but have 
been around the Rebol world for a while, mostly in lurk mode.  The 
reason that I am aware of for generating a layout prior to calling 
a view, is so you can dynamically build the layout.  Then, once all 
of the logic has constructed your dynamic layout, you view the entire 
peice together.

Maybe the advanced developers here have other reasons for this as 
well.

Hi Brock,  yes I think it boils down to some devs using VID and some 
using Faces and some even using a mix of both objects. Which according 
to the guide theres nothing wrong with !! But it's confusing for 
the newbs lol

Sorry I meant the View system - not Faces!!! See confused already 
lol

If you don't build the layout first, then you can't write functions 
that access the named widgets inside the layout.

Hi Graham, some dems say - main: layout [ .....   where other use 
main: make [...... would you usuall use make ??

sorry main: make layout [.....

I don't think I've ever used "make layout"

I've not used it in the main screen of my app and it works fine, 
just wondered if theres a reason to use it?

Think they use it to 'make face' when using the view system directly

Will, continuing from misplaced Tretbase thread...

Still not working...relations endure only so long as I don't end 
the engine's session.

Michael: notice the difference between mold and mold/all :
>> a: context [b: 1]

>> a/b
== 1

>> c: mold a

== "make object! [^/    b: 1^/]"

>> a: load c

== [make object! [
        b: 1
    ]
]

>> a/b
** Script Error: Invalid path value: b

** Near: a/b
>> a: do load c

>> a/b         
== 1

>> a: context [b: 1]
>> c: mold/all a
== "#[object! [^/    b: 1^/]]"
>> a: load c
>> a/b
== 1
>>

So, if I understand, the difference between mold and mold/all comes 
down whether I want to use the variables locally or or globally. 
But, in any event I need to use mold to preserve the object as a 
retrievable file? Is that correct?

home% rebol
>> do http://www.hmkdesign.dk/rebol/relationsengine/relations.r

>> add-relation [a 1 b 2]

== true
>> get-relation [a 1 b]
== [2]

>> save/all %relations.data relations
>> quit


home% rebol 

>> do http://www.hmkdesign.dk/rebol/relationsengine/relations.r
>> relations: load %relations.data
>> get-relation [a 1 b]

== [2]

>>
works!

read here for more info on the subject:
http://www.rebol.com/docs/changes.html#section-5.1

Ah, OK, that works for me too. Perhaps it was the code I was using 
to "look" at the data--

look: does[
    foreach word next first relations[
        print rejoin [word ":" newline get in relations word]
    ]
]


I will read the section you recommend. Thanks for your patience and 
help.

this also is very good reading:
http://www.fm.tul.cz/~ladislav/rebol/contexts.html

Thanks. I was just about to say that I can see now that it was the 
code I was using to imput the relations en masse that was causing 
my "look" code to not work. Amazing how talking things out can put 
things into perspective. Thanks again.

have fun 8) me going to zzz..

SteveT, using faces directly with MAKE is a lower level approach 
than LAYOUT. What LAYOUT does, is produce a face object that consists 
of many subfaces from your layout description written in the VID 
dialect. Each one of these face objects have settings for size, offset, 
appearance, text content, etc, which are set as the layout description 
is parsed. Using MAKE FACE directly provides greater control, but 
is more cumbersome to use, because you have to set all these values 
manually and arrange the face tree manually. You can see the content 
of the base FACE object in the console with:

>> ? face


The FACE object is the only object ever used, so it's a good idea 
to get to know it. You can extend it with more values and VID does 
this, to create variants, modes and extra operations on a face, like 
SET-FACE, GET-FACE, etc.


The reason why many choose to skip VID for this, is that VID doesn't 
provide the level of control needed as some things can't be determined 
properly at layout time, such as interdependency of sizes or offsets 
between faces, which is why VID doesn't support easy resizing out 
of the box.


Oh and when you get to try VID3 in REBOL3, forget everything I said, 
because it's a whole different system. :-)

Hi Henrik, thanks for that explanation.

main: layout [
        vh2 "Subpanel Examples"
        guide
        pad 20
        button "Panel 1" [panels/pane: panel1  show panels]
        button "Panel 2" [panels/pane: panel2  show panels]
        button "Quit" [quit]
        return
        box 2x140 maroon
        return
        panels: box 220x140 coal
    ]


Hi all, what does guide do above - I can't find it in the Dictionary

guide = "remember this cursor position"

Thanks again  Henrik

this means here, that it will affect how far to the left 'return 
will put the layout cursor

you can also use it like this:


view layout [button "hello" here: guide button "test" at here btn 
"boo!"]

Right so when you do return it will be kind of indented - Is it me 
or is guide not in the docs ???

it should be in the docs. which page are you reading?

I'm looking at the REBOL Dictionary

http://www.rebol.com/docs/view-system.html<--- for low level View, 
by the way

The dictionary doesn't contain dialected words, unfortunately

http://www.rebol.com/docs/easy-vid.html<-- this is an older, but 
fairly useful doc.

Yep - I read the View-System manual last night

what are dialected words ?

any words in a dialect

so you won't find BUTTON or GUIDE in the regular manual as they belong 
in the VID domain.

this is one of the major gripes about VID: I don't think there is 
one complete reference. Much of the information is either too old 
or dug up by probing inside SYSTEM/VIEW/VID to see what words are 
available in there.

Oh! right and VID could be replaced by rebGUI or whatever

yes, or your own dialect.

Pennies dropped !! Thanks Henrik