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Comment by aristus | Hacker News Reader

Back at the beginning of time I worked with Vignette StoryServer, which spun out of aolserver, one of the first "database-backed dynamic website" servers. The scripting language was TCL 7.something.

I never encountered it again, but its elegance always stayed with me. Except for uplevel. Fucking evil.

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Tcl might've been elegant but StoryServer most certainly wasn't. Http variables automatically injected into the code was a particularly fun security risk. Then they provided helpful (to hackers) error messages that could be googled. Still came up with a result all these years later! :-) http://www.google.com/#q=intitle%3A"StoryServer+Error"

uplevel allows you to write control structures like if, while, etc... in Tcl itself. Yes, that's something you need to be careful with because it's extremely powerful.

This is me, as well. TCL seems wierd and clunky when you come to it from C-derivatives, but once you get used to it, it's possible to write some very elegant code.

It gives you the capability to extend the language itself, something you can't really do in most other languages. Tcl, Forth and Lisp are the only ones I can think of. These days you get "monkey patching" and so on, but it's nowhere near as nice.

Rebol, Smalltalk, Perl6 and Io are some other examples that have the capability to (easily & cleanly) extend the language itself.

re: uplevel - Interesting Perl5 has this feature via a CPAN module! - https://metacpan.org/pod/Sub::Uplevel Also another variation is https://metacpan.org/pod/Scope::Upper

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