+++ /dev/null
-scheme.forth.jl
----------------
-
-A hobby Scheme interpreter for FORTH 83. Specifically it is targeted at
-[forth.jl](http://github.com/tgvaughan/forth.jl) which is an implementation of
-FORTH on top of [Julia](http://www.julialang.org), hence the name. It began
-life as a fairly direct port of Peter Micheaux's [Bootstrap
-Scheme](https://github.com/petermichaux/bootstrap-scheme) (as described in
-[this wonderful series of blog
-posts](http://peter.michaux.ca/articles/scheme-from-scratch-introduction)) from
-C to forth, but also includes:
-
-* variadic compound function support,
-* pre-evaluation syntactic analysis,
-* mark-sweep garbage collection,
-* quasiquotation,
-* a basic (non-hygienic) macro system and
-* first-class continuations via `call-with-current-continuation`.
-
-In future, I plan to also implement a more complete numerical tower to
-bring it closer to [R5RS](http://www.schemers.org/Documents/Standards/R5RS/).
-
-The goal is for the interpreter to be complete enough to be used to complete
-the majority of the exercises found in [SICP](http://sarabander.github.io/sicp/).
-
-Running the interpreter
-=======================
-
-To run this Scheme interpreter, first open Julia (**version >=0.6**) from the src
-directory contained in this repository. If you've not done so already, install
-forth.jl using the following command:
-
- julia> Pkg.clone("https://github.com/tgvaughan/forth.jl")
-
-Then, import and run the Forth system:
-
- julia> import forth
- julia> forth.run()
- Welcome to forth.jl!
-
-Once Forth is running, execute the Scheme source and fire up the
-REPL using the following commands:
-
- include scheme.4th ok
- scheme repl
- Welcome to scheme.forth.jl!
- Use Ctrl-D to exit.
-
- >
-
-At this point you can start entering Scheme commands. For example,
-
- > (define (factorial n)
- (if (= n 0)
- 1
- (* n (factorial (- n 1)))))
- ; ok
- > (factorial 5)
- ; 120
-
-Metacircular Evaluator
-======================
-
-Of course, one of the things you can do in Scheme (or of course any programming
-language, this is the fundamental thing) is implement an interpreter for
-another programming language. The examples directory in this repository
-contains a verbatim copy of the source for the "metacircular" scheme interpreter
-from SICP. To load it, use the following command:
-
- > (load "../examples/metacirc.scm")
- ; ok
-
-Be prepared to wait a couple of minutes. When the interpreter finally loads, enter
-the following command to run it:
-
- > (driver-loop)
-
-You'll then be greeted by the following prompt:
-
- ;; M-Eval input:
-
-At this point you can start entering Scheme commands... but be prepared to wait
-a while for each result. After all, when evaluating commands in the MCE you are
-running a program in a Scheme interpreter running inside another Scheme
-interpreter which is itself running on a Forth system that is implemented atop
-a virtual register machine running in the Julia numerical computing
-environment. **That's four levels of abstraction more than a native Julia
-program experiences**, so some delay is to be expected!
-
-For instance, the following example from SICP defines and demonstrates a
-recursive list append procedure:
-
- (define (append x y)
- (if (null? x)
- y
- (cons (car x)
- (append (cdr x) y))))
-
- ;;; M-Eval value:
- ok
-
- ;;; M-Eval input:
- (append '(a b c) '(d e f))
-
- ;;; M-Eval value:
- (a b c d e f)
-
-You may have to wait a minute or so for the final result to be printed.
-
-License
-=======
-
-This software is free (as in freedom) and is distributed under the terms
-of version 3 of the GNU General Public License. A copy of this license
-is included in this repository in the file COPYING.
The Lambda Lab / projects / scheme.forth.jl.git / blobdiff