Re:Tcl Static Prime: experimental compiler for Tcl that prod...
by davidw on Tuesday July 28, 2015 @04:29PM
(#9964268)
There is also an updated version out (with my name on the cover, to boot:-)
Although even that is not super recent.
Tcl's C API is very pleasant to work with, and its C code is a good read - except for the regex stuff, which are the first few files you'd see in an alphabetical listing.
Also look at the the source files for the Tcl (tclsh) or Tk (wish) shells. They are fairly concise.