Tcl has stopped being everything a string with the release of Tcl 8.0 and bytecode engine.

> In earlier versions of Tcl, strings were used as a universal representation; in Tcl 8.0 strings are replaced with Tcl_Obj structures ("objects") that can hold both a string value and an internal form such as a binary integer or compiled bytecodes.

http://www.ira.inaf.it/Computing/manuals/tcl/man-8.0/Changes...

I remember this quite well, because as part of the core team tasked with writing native C extensions, the migration to Tcl 8 had quite an impact on our code.

I learned Python with version 1.6, and have a few O'Reilley books proving the point the language wasn't really that simple, those that never bothered reading the reference manuals end-to-end though it was.