Recoil

Modules

A module starts with a Recoil [...] header that declares its type, id, imports, and exports. Imports may pull specific names from a module:

Recoil [
    Type: module
    Module: tests/math-module-demo
    Imports: [
        std/math/core [abs-value clamp-value]
    ]
    Exports: []
]

print abs-value [i32!] -7
print clamp-value [i32!] 10 0 5

Some modules (extensions) are called through a namespace prefix instead of importing individual names — see Extensions.

The package manager

Recoil ships a dependency workflow driven through the same CLI. A workspace has a recoil.project manifest and a generated recoil.lock.reb lockfile.

r3 -s recoil.r3 init
r3 -s recoil.r3 fetch
r3 -s recoil.r3 run app.rcl

On success, package commands print exactly one Rebol value (tagged Recoil-Init, Recoil-Fetch, …) that can be loaded directly for scripting. Failures use the standard CLI diagnostics.

Exporting functions

Mark functions with #export in the spec to expose them from a generated library. An init function (if defined) runs when the library loads.

add: func [#export a [i32!] b [i32!] return: [i32!]] [return a + b]
sub: func [#export a [i32!] b [i32!] return: [i32!]] [return a - b]
init: func [#export return: [none!]] [print "Library loaded!"]

Building libraries

Compile a source file to a shared or static library:

r3 -s recoil.r3 --lib mylib.rcl              # shared, name from source
r3 -s recoil.r3 --lib mylib.rcl --name mylib # shared, custom name
r3 -s recoil.r3 --lib mylib.rcl --static     # static

Given mylib.rcl, the compiler produces the C source mylib.c, a header mylib.h with the exported declarations, and the library itself (.so/.dylib/.dll for shared, .a/.lib for static — auto-detected per platform).

Using it from C

// main.c
#include "mylib.h"

int main() {
    init();                       // run library init if defined
    int32_t r = add(1, 2);
    printf("%d\n", r);
    return 0;
}

gcc -o myprogram main.c -L. -lmylib   # shared
gcc -o myprogram main.c libmylib.a    # static

Extensions

Extensions under the ext/ tree wrap C libraries behind a Recoil module. They are imported by module id and called through a namespace prefix. For example, ext/sqlite:

Recoil [
    Title: "sqlite demo"
    Imports: [ext/sqlite]
]

db: ext/sqlite:db-open ":memory:"
if none? db [print "open failed"]

stmt: ext/sqlite:prepare-stmt db "select ? + ?"
ext/sqlite:bind-int stmt 1 10
ext/sqlite:bind-int stmt 2 20
if ext/sqlite:stmt-step stmt = ext/sqlite:row-code [
    print ext/sqlite:column-int stmt 0     ; 30
]
ext/sqlite:stmt-finalize stmt

Writing your own extension (foreign declarations, type mapping, refinement patterns, one-shot vs handle wrappers, build/link choices, and a test pattern) is covered in the repository's extension authoring guide.