\documentclass[]{article}
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\title{TIP \#6: Include [Incr Tcl] in the Core Tcl distribution}
\date{October 16, 2000}
\author{Mark Harrison}
\urlstyle{sf}
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\begin{document}\maketitle
\begin{center}\begin{tabularx}{\linewidth}{|r@{: }X|}\hline
\textbf{TIP \#6}&\textbf{Include [Incr Tcl] in the Core Tcl distribution}\\\hline
Author&

Mark Harrison \tipmail{markh}{usai.asiainfo.com}
\\
Created&Monday, \(\text{16}^{\text{th}}\) October 2000\\
Type&Project\\
Tcl Version&\(8.4.0\)\\
State&Rejected\\
Vote&Done\\
Version&\tipversion$Revision: 1.6 $\\
Post History&\\
\hline\end{tabularx}\end{center}
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\begin{tipabstract}

Include [Incr Tcl] in the Core Tcl distribution.
\end{tipabstract}
\tableofcontents\setcounter{page}{0}\clearpage\pagestyle{plain}

\section{Proposal}

[incr Tcl] [\url{http://tcltk.com/itcl/}] shall be included in the core Tcl distribution. It shall be included in the Tcl source tree, and built as part of the standard Tcl distribution.

Specific items:
\begin{itemize}
\item{}
 ``itclsh'' will not be included
\item{}
 ``itcl\_*'' commands will not be included
\item{}
 everything will move from ::itcl to ::
\item{}
 the ``find'' subcommands will be reintegrated into ``info''
\end{itemize}

\section{Rationale}

The lack of a standard object and data abstraction system continues to hinder Tcl development.

\begin{quote}
``Lets face it, not including any sort of OO system is one of the major failings of Tcl. Indexing into global arrays is a sad hack when compared to a real OO system.'' \textit{- Mo DeJong \tipmail{mdejong}{cygnus.com}}
\end{quote}

Earlier this year, it seemed that it would finally be included in Tcl 8.4, but that plan was rescinded.

Note that this is distinct from the ``batteries included'' (BI) distribution, and is not intended to be a model for building the BI distribution. It is a special case for inclusion in the core tcl command set, since a ``class'' command is a fundamental language construct.

\section{Alternatives}

Include [incr Tcl] in a ``batteries included'' (BI) distribution.

Many people will not opt for the BI distribution (\cite{tip4}) due to its larger size. It is quite likely that (for example) a Linux distribution my include Tcl as a standard component, but place the BI on a supplemental disk.

\section{Objections}

\textit{I don't want any object system included!}

You can delete the [incr Tcl] library with no harm to your code.

\textit{John Ousterhout hates objects!}

This misconception is primarily due to a misreading of one of his papers. A better summary of his position is that ``scripting is a better solution than objects in many cases.'' John Ousterhout has told me that he will not stand in the way of adding object-oriented programming to Tcl.

\textit{[incr Tcl]'s object model is not good!}

[incr Tcl] supports the same object model as C++ and Java. Many programmers are familiar with this model and accept it as a good model.

\textit{The CLOS object model is better!}

Quoting John Ousterhout, ``People vote with their feet''. For whatever reason, slot-based systems failed to gain as much popularity as C++/Java-like systems.

\textit{There are many Tcl object systems to choose from!}

None are even a fraction as long-lived, popular, or well-supported as [incr Tcl].

\section{Special Provisions}

Since [incr Tcl] still exists as a separately named entity, this TIP shall not be construed as relieving any individual from the responsibility of providing appropriate [incr Apparel].

\section{Copyright}

This document has been placed in the public domain.

\section{Colophon}

\textit{TIP AutoGenerator --- written by Donal K. Fellows}
\begin{thebibliography}{TIP \#1}
\addcontentsline{toc}{section}{References}
\bibitem[TIP \#4]{tip4}
Brent Welch,
Donal K. Fellows,
Larry W. Virden,
Larry W. Virden,
\emph{Tcl Release and Distribution Philosophy},
on-line at \url{http://purl.org/tcl/tip/4.html}
\end{thebibliography}
\end{document}
