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Originally published in The Smalltalk Report, November 1995.
Smalltalk With Style
a book review by Jan Steinman and Barbara Yates
Smalltalk With Style, Suzanne Skublics, Edward J. Klimas, David A. Thomas. 1996 by
Prentice-Hall, Inc. 127 pages with index. $15.00 US.
Book Review by Jan Steinman and Barbara Yates
In our June 1995
column (Managing Project Documents 1 ) we mention
the importance of having a style guide within your organization, but
we weren't able to suggest any that you could walk into a bookstore
and take home. Until now, we have pointed our clients to a 1986
OOPSLA poster paper by Roxie Rochat and an internal Allen-Bradley
Smalltalk style guide by Ed Klimas as starting points. This book
fills the gap, and is long overdue. It belongs with every Smalltalk
Smalltalk with Style is not an "intro to Smalltalk" book. The
authors provide references to several other texts for the novice to
read to become acquainted with Smalltalk dialects, but this book is
mostly dialect-independent, which deserves special applause.
How to Use the Book
The 126 guidelines are grouped into five chapters by topic: naming
(guidelines 1-34), comments (guidelines 35-48), formatting
(guidelines 49-69), reuse (guidelines 70-90), and tips (guidelines
91-126). A glossary includes basic terms, and the Preface includes
some good stuff that should not be skipped.
This book should be read cover to cover the first time, rather
than used strictly as a reference book with random access to
guidelines via the index, because the prose leading up to the
numbered guidelines is essential to grasping the authors' full
meaning for the guideline. The examples following most guidelines are
required reading too! Finally, there are boxed notes or "tips"
sprinkled throughout the chapters that contain very helpful
A recent thread in comp.lang.smalltalk about Smalltalk code
formatting shows how religious an issue such a topic is; the same is
true about a lot of the guidelines in this book. You'll find
experienced Smalltalkers have strong opinions both favoring and
opposing some of these guidelines. This book's value is not in
dictating a standard to be followed, but in collecting in one place
the combined wisdom of many Smalltalk programmers who have been
writing and reading Smalltalk code for over a decade.
Some guidelines may appear deceptively obvious. You may ask
yourself "who would think of doing such a thing?" when
reading some of the bad examples. Even simple guidelines that
experienced Smalltalkers take for granted may be novel ideas to
brand-new Smalltalkers, and our experience in helping organizations
adopt Smalltalk shows that not a single guideline in this book is too
Some of the guidelines will be mis-applied by novices without
careful attention to their accompanying examples. One such case is
the recommendation to use parentheses to improve readability. Some
novices will use this as an excuse to avoid learning the simple
Smalltalk precedence rules, but the examples clearly show use and
abuse of parentheses. Don't expect this to be a Smalltalk programming
instructional manual -- it isn't intended to be.
Diplomacy vs. Dogmatism
The writers are not overly dogmatic, recognizing that certain
issues are largely a matter of individual taste. For example, on page
41 they state "There is no absolute way to indent and align Smalltalk
code. It is more important to be consistent within your code and,
when changing someone else's code, to be consistent with their code."
One unfortunate effect of this diplomacy is that in places the
book appears to bend over backwards to avoid stating a preference --
there are eight code fragments to illustrate the alignment
of brackets for Guideline 61, which then states "Choose one way
to align brackets in blocks and use it consistently. " This
statement of a guideline backed up by alternate ways to apply it
illustrates one of the points made in the introduction: "This
book should be used as the first draft for your own guide to good
Smalltalk style... The best guidelines are those that people want to
follow because they appreciate the benefit. Blind enforcement of a
matter that is of personal taste is not in the interest of the
project as a whole. "
Although the book is dialect-independent for the most part, we did
notice guidelines that are unnecessary in many Smalltalk development
environments. For example, a line length limit for source code is
suggested, but is a nuiscance in the majority of Smalltalk
environments that have re-sizeable, auto-wrapping code windows.
Rather than attempting complete dialect neutrality, it would have
been nice if the authors had pointed out the dialect implications of
This suggests the need for additional style rules in your
organization that are dialect and toolset dependent, for
example, specific naming conventions for ENVY applications and
version names. Keep in mind (as the authors point out), that this
book is a starting place for your organization, not a coding style
bible to be adopted as-is.
For us, the most enjoyable section of the book is chapter 5:
Tips, Tricks, and Traps . Unlike the guidelines in the
preceding sections, which are open to argument and sometimes
controversial, these guidelines are mostly universally accepted and
of particular importance to beginning Smalltalkers. Some of these
guidelines are meant to help you avoid some of the "classic Smalltalk
bugs" such as modifying a collection while iterating over it, or
forgetting to send yourself after a succession of
cascaded add: messages to a new collection.
Regrettably, some guidelines in this section cover important
topics such as testing in a superficial way. Perhaps it is more
important that something be said on these topics, albeit
very little, with further guidelines in these areas left up to the
readers to develop. Once again, this book is a template for you to
complete, not an all-inclusive tome.
Although we unreservedly recommend this book, we have some wishes
for a second edition. It could benefit from the eye of a professional
book designer, since the layout is a bit unapproachable and difficult
to scan, with numerous widows and orphans and a fussy indentation
scheme. (Contrast this to an absolutely gorgeous book that is similar
in concept: 201 Principles of Software Development ,
Alan M. Davis, 1995, McGraw-Hill, which also should be on everyone's
There were also a very few outright inaccuracies, such as the
glossary definition of a class instance variable. (Class instance
variable are not shared by instances of the class.)
Also strangely lacking (given two of the authors are at OTI,
makers of ENVY) are guidelines regarding the temporal aspects of
development, which is in many ways unique to Smalltalk. Certainly
more could be said on this topic than "Guideline 120: Avoid
modifying the existing behavior of base system classes ,"
without turning into an ENVY ad!
Many of the guidelines lack context and background. This is
probably necessary to keep it from ballooning into a general-purpose
Smalltalk how-to book, but the lack of "why" behind some of these may
cause unnecessary resistance in following them.
It should be taken as a tribute to this book that our criticism
can be largely boiled down to "more, please!"
To give you an idea of what the book is like, here are some of our
favorite guidelines, and some that we found most controversial.
- Guideline 26: Do not use the same temporary variable
name within a scope for more than one purpose. This is one
of those "motherhood" guidelines that should be obvious, but we
see it violated every day, particularly by new converts to
Smalltalk from C or FORTRAN.
- Guideline 40: Maintain the method comments with as much
care as the source code and keep them synchronized. Amen!
This is the "constant accuracy" principle of documentation we
describe in our
- Guideline 104: Test classes as they are
developed. and Guideline 105: Test components as they
are integrated. Testing is one of the great lies: "The
check is in the mail," "I'll still love you in the morning," and
"It's done (except for testing)." Expect testing to take on
renewed importance as many large, first-generation Smalltalk
projects enter their second iteration.
More controversial is the example under guideline 59 shown as a
"bad choice" because "although the Blue Book... uses this
style, most programmers [keep the left bracket on the line
[number <= 100] whileTrue:
["more code here
This is an example of the hidden dialect bias we would have
preferred was explicit. The built-in VisualWorks formatter makes your
code look similar to this "bad" example, and "most programmers" with
a VisualWorks, Objectworks, or Smalltalk-80 background are likely to
code in the "bad" style -- it should not be discouraged in such
We also find many of the bracketing and indenting styles would be
alien (or go missing) to someone whose only Smalltalk exposure was a
Smalltalk-80-family image. For example, an important missing
Smalltalk-80 guideline is to not line up columns of text with tabs,
since the use of different fonts will obliterate the horizontal
Guideline 64: Separate cascaded long key word messages with
a blank line or further indent subsequent keywords after the first if
the message has multiple keywords. Example: [complies with
with: #(a b c d e f g)
with: #(a b c d e f g)
Vertical white space is usually precious resource, and we prefer
guidelines that conserve it over guidelines that tend to make you
scroll. This example also shows the "narrow, non-wrapping window"
dialect bias, and a Smalltalk-80 programmer would probably keep each
message on the same line, with no extra whitespace.
Guideline 119 regarding lazy initialization does not address its
real value: providing state sequence independence. Better would have
been a brief discussion of base and derived state and a guideline to
"eagerly" initialize base state, while "lazily" initializing derived
state, but this once again treads the fine line between a style guide
and a design guide.
Before looking at the book, we asked ourselves some questions that
we've heard from novices. Happily, this book answered all that
strictly concerned style, but missed some that sit on the line
between style and design:
- Should I always write instance methods and create a single
instance of a class, rather than treat the class as a global and
write only class methods?
- What kind of behavior normally belongs on the class side?
- How do I decide which type of collection to use in my
application -- anArray, anOrderedCollection, something else?
Admittedly these are not really style questions, but this book
does cross the line from style to programming and process guidelines
at various times.
We don't envy the authors their task of choosing what to put in
and what to leave out. All in all they did an admirable job, and it
is with pleasure that we look forward to reading the "revised and
enlarged" edition which will surely come in the future.
At least one copy of this book belongs with every Smalltalk
Go to the previous
column in the series, or the next
column in the series.