Very Newbie questions

I am brand spanking new at Smalltalk.

I started last Friday with "The Dolphin Smalltalk Companion", but find I
need some preliminary work on the syntax, etc. I have looked around for some
books, and it seems that Chamond Liu is the best book to start with. Does
anyone have other suggestions? Unfortunately, not many books have been
written on Smalltalk.

I will be doing a lot of small exercises. How do I get back to the original
image? (I did not backup the default image right after installing, so it
already has some of the classes from the book in it. Do I have to uninstall
and reinstall?

Can I delete classes from an image, or do I have to backup to a previously
saved image, etc. to do that?

Are all the prepackaged classes that come with Dolphin standard procedure
for ST environments, or Object-Arts variation?

Why do many people mention Smalltalk with such respect, and then use C++ or
Java, or the MicroSoft stuff? At first blush, ST looks very good to me.

The Dolphin Smalltalk companion seems like a good investment. A copy of the
DVE and a book to boot for half the price of the DVE. A good marketing
tactic IMO. I may very well end up investing in one of the better versions.
I also like the author's approach. I find that I learn best when working on
an application. Little examples do not give the overall picture.

Jim,

> I started last Friday with "The Dolphin Smalltalk Companion", but find I
> need some preliminary work on the syntax, etc. I have looked around for
some
> books, and it seems that Chamond Liu is the best book to start with. Does
> anyone have other suggestions? Unfortunately, not many books have been
> written on Smalltalk.

Take a look at the AdviceToBeginners page on the Dolphin Wiki.


> I will be doing a lot of small exercises. How do I get back to the
original
> image? (I did not backup the default image right after installing, so it
> already has some of the classes from the book in it. Do I have to
uninstall
> and reinstall?

The Wiki also contains some good info on backups and crash recovery :)
Depending on the version of Dolphin, there might be a "Fresh install" start
menu item; if it's present, that will probably do what you want.


> Can I delete classes from an image, or do I have to backup to a previously
> saved image, etc. to do that?

You can delete classes.  You might want to make a backup before doing it
though.  With that said, your change log will contain the code until you
compress changes.


> Are all the prepackaged classes that come with Dolphin standard procedure
> for ST environments, or Object-Arts variation?

Dolphin contains many Windows specific packages, and many of those rely on
its MVP framework.  Sometimes other systems have similar capabilities.


> Why do many people mention Smalltalk with such respect,

Because it's worthy of it :)

> and then use C++ or
> Java, or the MicroSoft stuff?

I use C++ for things that require speed, and/or to re-use code.  I am
currently working on a system that uses Word to print.  That will be
replaced with my own code ASAP, but I needed a way to get going quickly, and
Automation control of Word was a way to do it.


> At first blush, ST looks very good to me.

I doubt you'll get too many disagreements here.  Welcome aboard!

Have a good one,

Bill

--
Wilhelm K. Schwab, Ph.D.
[hidden email]

Jim Jennings wrote:

> I am brand spanking new at Smalltalk.

Welcome!


> I will be doing a lot of small exercises. How do I get back to the
> original image? (I did not backup the default image right after
> installing, so it already has some of the classes from the book in
> it. Do I have to uninstall and reinstall?

You can get a clean image by doing a "fresh install" from the Dolhphin start
menu.  You don't need to re-install the Dolphin program itself.  To make a copy
of an image, say it's called "Working", you need to make copies of the three
files:
    Working.img
    Working.sml
    Working.chg
You can ignore the "Working.errors" file since it only contains a record of
each runtime error (normally resulting in a walkback dialog).  Be careful to
keep these files in synch (if you make backups at all) since the .IMG file
contains pointers into the .SML and .CHG files.

The simplest way to do non-destructive experimenting is just not to save the
image as you exit Dolphin; that will result in *all* the changes you've made
(since you last saved) being discarded.  Actually there is still a record of
what you did in the .CHG file, and -- sooner or later -- you will find yourself
needing to recover changes/actions from that file.  Ian Bartholomew's Chunk
Browser is the best tool for doing that; the version for Dolphin 4 should be
at:
    http://www.idb.me.uk/goodies4/goodies4.html


> Can I delete classes from an image, or do I have to backup to a
> previously saved image, etc. to do that?

You can delete them as you wish.  Not a good idea to delete, say, String
however...

BTW, I'd advise you to get into the habit of putting all classes (and any other
new code) into packages straight away.  Unless it is genuine throwaway code
that you know you'll never want to think about again.


> Are all the prepackaged classes that come with Dolphin standard
> procedure for ST environments, or Object-Arts variation?

There's a fair amount of commonality between Smalltalks for the core stuff
(like the Collections hierarchy), but, e.g, the GUI systems tend to be
completely different from one Smalltalk to another.  As a *very* rough rule of
thumb, if any two ST implementations are the same in some respect -- have the
same classes or whatever -- then the chances are that Dolphin will be the same
as both of them.  If any two differ in some respect then it's quite likely that
Dolphin will be different again from both of them.  (This is a point to bear in
mind when you read Lui's book -- if you do -- since he discusses two or three
other implementations, but not Dolphin.)


> Why do many people mention Smalltalk with such respect, and then use
> C++ or Java, or the MicroSoft stuff? At first blush, ST looks very
> good to me.

Market forces, ignorance, predjudice, inertia...

And personal preference too, of course.


    -- chris

Thanks Bill and Chris. I am emersed in the Education Centre lessons. I am up
to my eyeballs in classes. So much to learn!