[Treblemaker]

> It fakes having numbers, which works, but has to be slow.

This hasn't been the case for 25 years, since the 8.0 release. Tcl will store data internally in whatever format it was last used, and only convert if needed. Good coding practice pays attention to this to avoid "shimmering" a value back and forth between different internal representations unnecessesarily.

> It lacks arrays;

It does have associative arrays; and lists when used appropriately can fulfil many roles that would otherwise have been implemented in an array in another language

And tcllib[0], a collection of utilities commonly used with tcl, provides support for a number of different and complex data structions [1], many of which are written in C, not just more tcl scripts.

It's worth noting that Stallman's criticism linked above is more than three decades out of date. As with any programming tool, once you go beyond a superficial understanding of basic syntax, it can serve as a a very expressive and sufficient language.

[0] <https://www.tcl-lang.org/software/tcllib>

[1] <https://core.tcl-lang.org/tcllib/doc/trunk/embedded/md/toc.m...> (see: Data structures)