The LA Fox Developer Newsletter

July. 1994

The LA Fox Developer is the monthly newslet-

ter of the LA Fox User Group. The purpose is

information sharing among application develop-

ers and users working with FoxPro.

LA Fox Address:

LA Fox User Group

Chuck Williams

(310) 539-9439

977 Ashbndge Lane

Harbor City, CA 90710

LA Fox Board of Directors

Chuck Williams, President

David Van Valkenburg, Treasurer

Allen Garfein, Membership

George Dvorak

Warren Rekow

Bill Seldon

Barry Lee, Newsletter Editor

Gerg Dunn

Kris Dahlin

The newsletter contains regular columns and

articles from other user groups.

XPro User Group

Randy Unruh

(310) 399-9159

2210 Wilshire Blvd. - #161

Santa Monica, CA 90403

OC MS FoxPro Developers Group

John Miller

(714) 661-5264

Subscriptions

The annual membership fee for the LA Fox

User Group, including subscription to The LA

Fox Developer Newsletter, is $45.

Disclaimer

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Group, the OC MS FoxPro Developers Group,

their officers or board of directors or their

members make any express or implied warran-

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group. All opinions and information should be

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respective owners.

“waterfall” model of development and the rapid prototyping

approach. One of the major shortfalls of the traditional approach

is that the real users never see anything until the specification

process is complete and development is well under way. As Jim

pointed out, this often doesn’t work well because users are not

good at describing what they want and need unless they can

see it on screen and use it, so this almost guarantees a large

conflict between developers and users when users finally see

some tangible results. Rapid prototyping, on the other hand,

puts working screens in front of the user very early in the pro-

cess, and allows the “requirement” to evolve to something

closer to what users really need, before there is a big invest-

ment in developer effort and calendar time. This pays particu-

larly big dividends in client-server systems, by achieving stability

in definition of the backend database structure before starting to

build the many interrelated data objects and backend-frontend

connections.

Jim stressed the use of simple diagrams as a way to communi-

cate with users. He cited examples where reducing the “require-

ments” to diagrams, not only clarified the situation for develop-

ers, but also created great diversity of opinion within the client

organization about how their world really worked.

Jim shared his ideas about naming conventions, and said that

the most important thing was to have one, rather than what its

details are. He encouraged the “black-box” idea, where seg-

ments of code associated with a particular action are isolated by

such techniques as privatizing variables, to avoid invisible

interactions with the application environment, and to create

clear visibility to the designer. He said that “optimizing” should

not always favor performance, but should consider clarity,

development effort, and maintenance effort performed when the

original designer is gone. He also cautioned that sometimes

added complexity in the short term or narrow code segment is

worth it to simplify things in the larger application context.

Anyone who didn’t learn something useful in this session must

have been asleep. Thanks Jim for sharing with us.

And, fitting right in with this theme, the latest book in the Pin-

nacle Pros Talk Fox series just arrived, with the title FoxPro

Rapid Application Development. The author is Whil Hentzen,

another long time Xbase developer and frequent writer and

speaker at FoxPro events. He describes in detail his approach

to establishing a productive development environment and

using Core Foundation elements. His environment ideas in-

clude defining directory structures and managing test data. His

Core Foundation is a superstructure containing generic ele-

ments for the “main” initializing program, menu handling facility,

error trapping, help facility, security facility, lookup tables, and

(Con’t, page 3)

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