Forth for Tcl
I like Tcl. HolonForth is written in Tcl. Tcl provides a rich software ecosystem that is available on all popular computer platforms.
Tcl and Forth share a common philosophy. Both are based on words (or "commands") that implement the rules of the language. There is just one fundamental difference: Tcl uses prefix and infix notation, Forth uses postfix notation.
Postfix has remarkable consequences. A Forth program is a sequence of words that exchange their parameters on a stack.
In other words: Forth simplifies programming.
Forth in Tcl
HolonTForth uses Tcl as its native language. Tcl is an excellent companion to Forth.
- All Tcl and Tk features are available as Forth Code words.
- The parameter stack is used to transfer arguments and results between words. Inside words local variables are preferred. Stack parameters are converted to local variables at the start of a word. The local variables are defined in the stack notation.
- All standard Forth flow control words are implemented as well as foreach and switch in the form of a case construct.
- HolonTForth is a metacompiler. The Forth system and the Tk extensions are defined and loaded with the application. The system definitions can be changed and extended by the user.