Railroad diagram definition

[PIEBALD]

[This may not be on topic as it's not .net-specific, but I tried to find the
most general MSDN forum I could.]

I'm trying to find a general definition/specification for railroad diagrams.
All I find online are explanations by authors who explain what _their_
particular format uses, but they leave me wondering if they are using only a
subset of the possible structures. And there are a few that seem to use
rather unique structures.

Is there a standard? Does each author create his own? There must be a set of
dos and don'ts somewhere!

[Nick Malik [Microsoft]]

What is a "railroad diagram"? Are you talking about a sequence diagram?
If so, there are a number of good books on UML2 that will describe the
entire standard.

--
--- Nick Malik [Microsoft]
MCSD, CFPS, Certified Scrummaster
http://blogs.msdn.com/nickmalik

Disclaimer: Opinions expressed in this forum are my own, and not
representative of my employer.
I do not answer questions on behalf of my employer. I'm just a
programmer helping programmers.
--
"PIEBALD" <PI*****@discussions.microsoft.com> wrote in message
news:CD**********************************@microsof t.com...

[This may not be on topic as it's not .net-specific, but I tried to find
the
most general MSDN forum I could.]

I'm trying to find a general definition/specification for railroad
diagrams.
All I find online are explanations by authors who explain what _their_
particular format uses, but they leave me wondering if they are using only
a
subset of the possible structures. And there are a few that seem to use
rather unique structures.

Is there a standard? Does each author create his own? There must be a set
of
dos and don'ts somewhere!

[PIEBALD]

> What is a "railroad diagram"?

Exactly. And if Microsoft doesn't know...

Anyway, like Pascal syntax diagrams, they describe grammars. If you search
the web you can find lots of examples, but no definitive specification. The
closest I've found is at:

http://www.serve.com/~josh/books/jav...ef/ch01_05.htm

But even this really just gives a few simple examples. I guess it's
difficult to define a grammar for a diagram.

[Nick Malik [Microsoft]]

"PIEBALD" <PI*****@discussions.microsoft.com> wrote in message
news:1A**********************************@microsof t.com...

What is a "railroad diagram"?
Exactly. And if Microsoft doesn't know...

unfair. If Nick Malik doesn't know... Microsoft has 60,000 people. I speak
for one.

Anyway, like Pascal syntax diagrams, they describe grammars. If you search
the web you can find lots of examples, but no definitive specification.
The
closest I've found is at:

http://www.serve.com/~josh/books/jav...ef/ch01_05.htm

But even this really just gives a few simple examples. I guess it's
difficult to define a grammar for a diagram.

The link you provided gives you the answer: Railroad diagrams are simply a
visual representation for BNF. They are visual to make them easier to READ.
It says nothing about making grammars easier to write. My guess is that the
authors of this diagram are using it for illustration, but have no intention
of actually using it to create a new grammar. They would still use BNF for
that.

It is difficult to define a grammar for anything. Diagrams are not harder
than other mechanisms. UML is a diagramming grammar.

The fact that you cannot find a grammar for this diagram type may simply be
because no one was interested in using it for more than simple illustration.
(my guess only)
--
--- Nick Malik [Microsoft]
MCSD, CFPS, Certified Scrummaster
http://blogs.msdn.com/nickmalik

Disclaimer: Opinions expressed in this forum are my own, and not
representative of my employer.
I do not answer questions on behalf of my employer. I'm just a
programmer helping programmers.
--

[PIEBALD]

> > Exactly. And if Microsoft doesn't know...

unfair. If Nick Malik doesn't know... Microsoft has 60,000 people. I speak
for one.
That was just a dig.
The link you provided gives you the answer: Railroad diagrams are simply a
visual representation for BNF. They are visual to make them easier to READ.
It says nothing about making grammars easier to write. My guess is that the
authors of this diagram are using it for illustration, but have no intention
of actually using it to create a new grammar. They would still use BNF for
that.

Still, there ought to be a standard. Such a standard would further the ease
of understanding by the reader, one would not need to learn a whole new form
each time one reads a new document. It would also make it easier for the
writer as well.

At this point I have to read a number of such descriptions and distill the
various forms to find their similarities.