**How it started**

When looking for a frontend/client for [ATWF] and [Reporting Tools with Tcl] I did spend some time checking all the available stuff. For a [Tcl] client it was easy there I decided to use a [Tclkit]/[Starkit], but in a browser, the only existing possibility is the [Tcl/Tk plugin], but there I knew that there were some problems and it was not much updated in the past.
 
So I was thinking about generating [HTML] code on the server side with [Tcl]. At that time I was also checking what of the existing [javascript] based libraries could be used especially [jQuery] and [YUI]. Both had a lot of interesting features. I also found [Tcl in Javascript] and was thinking about using that as an interface for making either [jQuery] or [YUI] functionality available with a [Tcl] wrapper.

When looking closer at that and playing with it I did like it a lot, but was soon missing [Tcl] functionality I wanted to use.

That was the start of the [incr Tcl in Javascript] project. At the beginning I was only adding some (from my point of view) functionality, which I was missing most.

The general idea already used/implemented by Stéphane Arnold was to have TclObjects (TclObj) implemented as [javascript Object]s ([TclObject js Object]), which hold a [Tcl] value that can be converted into the different types needed like:

   * string
   * integer
   * real
   * boolean
   * list
 
I have added to these types:

   * dict
   * stmt
   * word
   * syllable
 
The „dict“ type holds - as in the Tcl C-implementation - the internal representation of a Tcl dictionary. 

I started with implementing [namespace]s. This was done by having a [javascript Object] [TclNamespace js Object] that did have properties for the relevant information and was used in a similar way as the TclNamespace struct in the C implementation. It contains references to the parent [namespace] and a list of the child namespace references. There was some basic implementation of a callframe available, I modified that to use a [TclCallframe js Object], which had additional properties like the currently executed statement for introspection, the used [namespace] for that callframe etc.

For [namespace]s also the [Tcl] parser ( [TclParser js Object]) had to be extended to understand the [namespace] syntax for command and variable names.

The [TclNamespace js Object] was designed to allow different types of namespace:
   * Tcl.NAMESPACE a “normal” [Tcl] [namespace]
   * Tcl.ITCL_CLASS an [itcl] class [namespace]
   * Tcl.ITCL_EXTENDED_CLASS an [itcl] extendedclass [namespace]
   * Tcl.TYPE_CLASS an [itcl] type [namespace]

For the [itcl] namespace types there was designed a resolve_commands reference for allowing implementation of namespace command resolvers. 

This Object includes method for registering class commands and for registering subcommands, which is used for implementing namespace ensembles. A list of superclasses is provided here as well as entries for a class constructor and a class destructor.

Later on there was added support for namespace variables which are handled with a reimplementation in [javascript] of the equivalent C-functions lookupVariableEx, lookupSimpleVariable, GetNamespaceForQualName and FindNamespaceVar.

(Part of [itcl in Javascript Paper])

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