Inline::Scheme::Gambit 
This is a Perl 6 module which allows execution of Gambit Scheme code from Perl 6 code with inspiration from other Inline:: modules like Inline::Python, Inline::Lua, Inline::Scheme::Guile, etc.
Synopsis
use Inline::Scheme::Gambit;
my $gambit = Inline::Scheme::Gambit.new;
my $code = q:to/END/;
(define (fib n)
(if (< n 2) n (+ (fib (- n 1)) (fib (- n 2)))))
END
$gambit.run($code);
say $gambit.call('fib', 8);
say $gambit.call('map',
$gambit.run(q{(lambda (n) (fib n))}),
[0 .. 8]);
Status
Testing has only been done under Rakudo MoarVM on x86-64 Linux. It requires Gambit-C 4, and Gambit-C 4.8.3 and 4.2.8 have been tested by the author.
Values can be passed to and returned from Gambit-C. Simple types like boolean, integer, number, string, list, table, vector should work. Present mapping between Gambit-C and Perl 6 types is as following table.
Gambit-C from Perl to Perl
boolean Bool Bool
integer(exact) Int Int
rational(exact) Rat Rat
rational(inexact) Num Num
complex Complex Complex
string Stringy Str
list Positional Array
table Associative Hash
vector Array
procedure OpaquePointer
other objects OpaquePointer OpaquePointer
Note that at present both scheme list and vector converts to Array in Perl 6, but through the call() method (see below) Perl 6 Array only converts to list.
The API is incomplete and experimental. It may change in future if necessary.
To Do
- Think about wrapping OpaquePointer for scheme-object, so that it can do better on scheme list/vector/procedure/etc.
- Support scheme record type.
- Improve error handling.
Install
panda install Inline::Scheme::Gambit
It by default tries to use 'gsc-script' or 'gsc' as the gsc command, and dynamically link to libgambc.so. It supports several environment variables to override the default behavior.
For example to override gsc in case 'gsc-script' or 'gsc' is not in PATH, or 'gsc-script' is an incorrect symlink.
GSC=/usr/bin/gsc panda install Inline::Scheme::Gambit
Or if you would like to static link to some libgambit.a
LIBS=-lutil MYEXTLIB=/usr/lib/gambit-c/libgambit.a panda install Inline::Scheme::Gambit
You can refer to Makefile.in and Build.pm to know more details.
Usage
Inline::Scheme::Gambit
Object of Inline::Scheme::Gambit represents a global Gambit-C instance.
method new()
Returns the global Inline::Scheme::Gambit singleton. The first call to new() initializes the singleton.
method run(Str:D $code)
Runs $code and returns any resulting value.
method call(Str:D $name, **@args)
Calls the named function with @args, and returns any resulting value.