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= 1) Namespaces =
== Namespaces : Context ==
We need to create name spaces.[[BR]][[BR]] Namespaces are
 * a labeled/named subset of identified/labeled content,
  * content can then be precisely identified with a compound identfier
  * the conjuction of the subset name and the content name.
 * commonly structured as nested hierarchies to allow reuse of names in different contexts.
 * typically employed for the purpose of grouping symbols and identifiers around a particular functionality
  * to avoid name collisions between multiple identifiers that share the same name.
 * hierarchical, ie sets of namespaces can be nested within another namespace

== Namespaces : Examples ==
=== In TDX ===
'''{{{ NAMESPACE $project }}}'''[[BR]][[BR]]
Puts anything following in the current project context

'''{{{ NAMESPACE $project:subComponent }}}'''[[BR]]
OR[[BR]]
'''{{{ NAMESPACE subComponent }}}'''[[BR]][[BR]]
Puts everyting that follows into the project's subComponent namespace

'''{{{ NAMESPACE subComponent - $system:language }}}'''[[BR]]
OR[[BR]]
'''{{{ NAMESPACE subComponent - language }}}'''[[BR]]
OR[[BR]]
'''{{{ NAMESPACE subComponent - $dxlib:codelib }}}'''[[BR]][[BR]]
Puts everything that follows into the project's subComponent namespace AND incorporates the system defined "language" namespace contents accessible to the project.

==== NB. ====
The default namespace is $project and coresponds to the base directory of the current project.[[BR]]
The default namespace to be included is $system and coresponds to a file refererd to by the dxiner environment variable.[[BR]]
If any other $name is used, it coresponds to a system based environment variable containing a directory where the coresponding ".tdx" file can be found. The variable can consist of a selection of paths, separated by semi-colons.

=== In VDX ===
== Namespaces : Semantics ==
== Namespaces : Data Definition ==
To store namespaces we need a structure similar to that detailed below ... [wiki:NotationExplaination explaination of the notation]

=== In TDX ===
{{{
NAMESPACE $project:tdx - $system:lang 
  // however $project is implied and not really needed

  SINGLETON design
    namespace ourNameSpaces = NEW namespace("system")

    SYNTAX
      textualDesignClause := ( designClause )+;
      designClause := namespaceClause ( designComponentClause )+;
      designComponentClause := ... ;

  CLASS namespace(ubyte$ name)
    namespace{} subSpaces
    
    namespace(namespace) addNamespace(newNameSpace) =
    {
      subSpaces->add(newNameSpace)
      RETURN newNameSpace
    }

    SYNTAX
        namespaceClause := "NAMESPACE" newNameSpaceClause 
          ( "-" ( existingNameClause )+ );
        newNameSpaceClause := ( "$" ident ( ":" ident )* | ident ( ":" ident )+ );
        existingNameClause := ( "$" ident ( ":" ident )* | ident ( ":" ident )+ );
}}}
=== In VDX ===
[[Image(namespace.png,width=98%)]]

== Namespaces : Syntax ==
=== INFORMATION MODEL ===
=== '''PROCEDURAL MODEL''' ===
[[Image(namespaceClause.png,width=98%)]] [[Image(newNamespaceClause.png,width=98%)]] [[Image(existingNamespaceClause.png,width=98%)]]

== (2) [wiki:TypeDefinition Types] ==
== (3) [wiki:EnumDefinition Enums] ==
== (4) [wiki:SignalDefinition Signals] ==
== (5) [wiki:SingletonDefinition Singletons] ==
== (6) [wiki:ClassDefinition Classes] ==