Re: Suffix _T for types found good

[Georg Bauhaus <rm.tsoh.plus-bug.bauhaus@maps.futureapps.de>]

amado.alves@gmail.com wrote:

> And even if you can come up with good different names for types and
> objects, even if you magically did that effortlessly, why double the
> lexicon? Can it possibly make the code better? Just to avoid a suffix
> rule?

Some points of reference for choosing names, collected
here and there.  They are not perfect rules, but I
think they make sense:

- Can you answer the questions,
[a]   "What kind of Node are these?"  -> secific type
[b]   "What kind of Node is this one?" -> specific object

A type in the sense of [a] comprises many things and
is possibly served well by a generic term. At first sight,
"Node" is such a term: assigning different meanings to "Node"
is easy. Too easy. It doesn't say what kind of Node.

In a given program's context, the nodes refer to some
larger thing of which they form part.  This relation
may offer advice on chosing a qualification of Node.
A package name can serve as a qualifying addition.
There may even be another word that somehow includes
the notion of Node.

An object in the sense of [b] has identity. Identity is
usually designated by a locally unique specific name.
The name can allude to the specifics.  "Central_Star" or
even "Sun" are possibly better names than just
"Celestial_Body" or "Node", I should think.

The identity can be a bit of a formal identity.
For example, a subprogram parameter name designates a
specific object during each invocation. But there are
many invocations. Each gets a different specific node.
In this case,  a convention is to use the prefix
"The_" to indicate identity:

  procedure Foo(The_Node: ....);

The name here expresses that Foo is going to deal with
just one node, namely The_Node.   But when declaring
specific objects, e.g. nodes in certain roles,

  Junction: ...;
  Crossing: ...;


It seems to be tempting to just use some variation of
a type name for objects. Example:

   osw: OutputStreamWriter;  -- NOT!

is typical of programs targetting the JVM. So the reader
remembers that "osw" designates some output channel.
But which one?  The programmer was too lazy to think of
a name.  Points of reference: The purpose of this output.
Where does it end?  Which ends does it connect?