Re: define-language

[Matt Wette]

On 8/7/20 12:31 PM, Stephen Scheck wrote:
> What is the right way to use `define-language`? The Guile manual says that
> when using this form "the language will be added to the global language
> set." I interpret that to mean that the `,language` meta-command switches
> the REPL to use the newly-defined language, but it doesn't work:
>
> scheme@(guile-user)> (use-modules (system base language))
> scheme@(guile-user)> (define-language mylingua
>    #:title "Mylingua"
>    #:reader (lambda (port env) ...)
>    #:evaluator (lambda (x module) ...)
>    #:printer write)
> scheme@(guile-user)> mylingua
> $1 = #<<language> name: mylingua title: "Mylingua" reader: #<procedure
> 1bfcd38 at <unknown port>:5:11 (port env)> printer: #<procedure write (_
> #:optional _)> parser: #f compilers: () decompilers: () evaluator:
> #<procedure 1bfcd48 at <unknown port>:6:14 (x module)> joiner: #f
> for-humans?: #t make-default-environment: #<procedure
> make-fresh-user-module ()> lowerer: #f analyzer: #f compiler-chooser: #f>
> scheme@(guile-user)> ,language mylingua
> While executing meta-command:
> no such language mylingua
I usually use a reader and compiler (something that compiles to tree-il).
The important item to know is that the output of the reader is the input
 for the compiler.

I do have spec.scm files with evaluator but it's just the default I think.
I don't remember what the evaluator does but guessing it processes
input to the `eval' procedure.

Check examples/language  and examples/language/nyacc/lang/
in https://download.savannah.gnu.org/project/nyacc
or https://git.savannah.nongnu.org/cgit/nyacc.git/tree/

 I include examples for a calculator (calc), javascript (nx-javascript),
matlab (nx-mlang) and tcl (nx-tcl).  You can download and unpack the 
nyacc distribution.

$ cd examples
$ source env.sh
$ guile
guile> ,L nx-javascript
....
nx-javascript@(guile-user)> var a = 1;
nx-javascript@(guile-user)> a
$1 = 1
nx-javascript@(guile-user)>