Not necessarily in the reference implementation, but quite early:

Adam Sah, UCB: An Efficient Implementation of the Tcl Language (1994, UCB Masters Degree Thesis for Professor John Ousterhout):

https://www2.eecs.berkeley.edu/Pubs/TechRpts/1994/CSD-94-812...

After Ousterhout and his team went to Sun, but before the Java Juggernaut made its debut, Sun was positioning TCL to be the "Official Scripting Language of the World Wide Web".

Brian T. Lewis, Sun Microsystems Labs: An On-the-fly Bytecode Compiler for Tcl (1996, Usenix TCL/Tk Workshop):

https://www.usenix.org/legacy/publications/library/proceedin...

I wonder what would have happened if John Oosterhout's TCL team had applied Dave Ungar's Self team's JIT tech to TCL, before the Self team left Sun and made HotSpot (who Sun then hired back to apply to Java). Anyone know if / how those two teams at Sun overlapped / interacted at Sun Labs?

Then "The TCL War" happened, which didn't help TCL's world domination plans either:

https://vanderburg.org/old_pages/Tcl/war/

https://news.ycombinator.com/item?id=12025218

Slightly Skeptical View on John K. Ousterhout and Tcl:

https://softpanorama.org/People/Ousterhout/index.shtml

>There was some concerns about TK future. See for example the following message from [Python-Dev]

>FYI ajuba solutions (formerly scriptics) acquired by interwoven

On Tue, Oct 24, 2000 at 07:07:12PM +0200, Fredrik Lundh wrote:
>I'm waiting for the Tcl/Tk developers to grow up -- they still
>fear that any attempt to make it easier to use Tk from other
>languages would be to "give up the crown jewels" :-(

>In the long run this has probably harmed Tk seriously. If Tk was just a widget set divorced from Tcl, then it might have been chosen as the underlying widget set for GNOME or KDE, and then have benefited from the development work done for those projects, such as the GNOME canvas enhancements, which now can't be absorbed back into Tk without a lot of effort to merge the two sets of code.

The genius of TCL/Tk:

https://news.ycombinator.com/item?id=22709478

DonHopkins on March 28, 2020 | parent | context | favorite | on: Is there any code in Firefox (as of 2020) that com...

The genius of TCL/Tk, and the reason I believe Tk was so incredibly successful despite the flaws and shortcomings of TCL, is that toolkits like Motif, based on the X Toolkit Intrinsics, that aren't written AROUND an existing extension language, end up getting fucked by Greenspun's Tenth Rule:

https://en.wikipedia.org/wiki/Greenspun%27s_tenth_rule

>"Any sufficiently complicated C or Fortran program contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Common Lisp." -Philip Greenspun's Tenth Rule

The X Toolkit ends up needing to do all of these dynamic-scripting-language-like things, like resolving names and paths, binding events to handlers, calculating expressions, and instantiating objects based on resource data. So if it doesn't already start out with a standardized scripting language to use for that, it has to duplicate all that dynamic almost-but-not-quite-entirely-unlike-half-of-Common-Lisp stuff itself.

Case in point: Motif's infamous UIL (because X resource files weren't half-assed enough).

https://www.donhopkins.com/home/catalog/unix-haters/hpox/uil...

And then when you do get around to plugging that toolkit into some other scripting language (the way WINTERP plugged Motif/Xt into XLisp, or GTK/GObject plugs into Python for that matter), now you have two or more fat bloated complex buggy poorly documented incompatible impedance-mismatched half-assed competing layers of middleware and object models tripping over each other's feet and spraying each other with seltzer bottles like the Three Stooges.

https://www.youtube.com/watch?v=VO9RP4QEZKU

https://news.ycombinator.com/item?id=22610342

>Speaking of the plague, does it support UIL? ;)

>Neils Mayer described WINTERP (XLisp + Motif) as: You might think of such functionality as "client-side NeWS without the postscript imaging model".

http://nielsmayer.com/winterp/

>Don Hopkins wrote to a comp.human-factors discussion about "Info on UIL (User Interface Language)" on January 22, 1993:

https://groups.google.com/d/msg/comp.human-factors/R3wfh90HM...

>Here are some classic messages about UIL. Avoid it like the plague.

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