Initial

Author: frmdstryr

.github/workflows/ci.yml

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+name: CI
+on: [push]
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - name: Install dependencies
+        run: |
+            sudo snap install --beta --classic zig
+            pip install pytest
+            zig version
+      - name: Build example
+        run: pip install ./example
+      - name: Test example
+        run: pytest tests

.gitignore

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+dist/
+build/
+__pycache__
+*.so
+*.pyc
+*.egg-info
+

README.md

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+# Lightweight Python ffi for zig
+
+py.zig provides a _lightweight_ interface for creating python extensions in zig. 
+
+It is intended to be used with [setuptools-zig](https://pypi.org/project/setuptools-zig/) by
+simply cloning or copying `py.zig` into your python project and 
+adding an `Extension` entry in your `setup.py`.
+
+
+
+```py
+from setuptools import Extension, setup
+
+setup(
+    name='pyzigtest',
+    version='0.1.0',
+    python_requires='>=3.10',
+    build_zig=True,
+    ext_modules=[
+        Extension(
+            'pyzigtest',
+            sources=[
+                'src/pyzigtest.zig'
+            ],
+            extra_compile_args=["-DOptimize=ReleaseSafe"]
+        )
+    ],
+    setup_requires=['setuptools-zig'],
+)
+```
+
+Then in your extension import `py.zig` and define the python module. 
+
+See the `/examples` for a complete example.
+
+## Why 
+
+py.zig is designed but a much lighter alternative to something like [ziggy-pydust](https://github.com/spiraldb/ziggy-pydust).
+

example/py.zig

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+../py.zig

example/pyzigtest.zig

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+const py = @import("py.zig");
+const std = @import("std");
+// Import basic objects
+const Object = py.Object;
+const Int = py.Int;
+const Str = py.Str;
+const Module = py.Module;
+
+pub fn add(mod: *Module, args: [*]*Object, n: isize) ?*Object {
+    _ = mod;
+    if (n != 2) {
+        return py.typeError("sum requires 2 arguments");
+    }
+    // We can now safely access  indexes 0 and 1
+    if (!Int.check(args[0]) or !Int.check(args[1])) {
+        return py.typeError("both arguments must be ints!");
+    }
+
+    // We can now safely cast to Int objects and access their methods
+    const a_obj: *Int = @ptrCast(args[0]);
+    const a = a_obj.as(isize) catch return null;
+
+    // Or use the method statically and do it in one step
+    const b = Int.as(@ptrCast(args[1]), isize) catch return null;
+
+    // Add them and create a new Int object
+    return @ptrCast(Int.fromNumber(a + b) catch return null);
+}
+
+
+fn modexec(mod: *py.Module) !c_int {
+    const stdout = std.io.getStdOut().writer();
+    const s = mod.str() catch return -1;
+    defer s.decref();
+    try stdout.print("modexec on {s}!\n", .{s.asString()});
+
+    // Add a str
+    const test_str = try Str.fromSlice("test!");
+    defer test_str.decref();
+    try mod.addObjectRef("TEST_STR", @ptrCast(test_str));
+
+    return 0;
+}
+
+pub export fn py_mod_exec(mod: *py.Module) c_int {
+    return modexec(mod) catch |err| switch (err) {
+        // py.zig uses error.PyError for any error caught from the python c-api
+        error.PyError => -1, // Python error
+        // Any other errors need to set an error in python
+        else => blk: {
+            _ = py.systemError("module init failed");
+            break :blk -1;
+        },
+    };
+}
+
+var module_methods = [_]py.MethodDef{
+    .{
+            .ml_name="add",
+            .ml_meth=@constCast(@ptrCast(&add)),
+            .ml_flags=py.c.METH_FASTCALL,
+            .ml_doc="Add two numbers"
+    },
+    .{} // sentinel
+};
+
+var module_slots = [_]py.SlotDef{
+    .{.slot = py.c.Py_mod_exec, .value = @constCast(@ptrCast(&py_mod_exec))},
+    .{} // sentinel
+};
+
+var moduledef = py.ModuleDef.new(.{
+    .m_name = "pyzigtest",
+    .m_doc = "pyzigtest module",
+    .m_methods = &module_methods,
+    .m_slots = &module_slots,
+});
+
+pub export fn PyInit_pyzigtest( _:*anyopaque ) [*c]Object {
+    return moduledef.init();
+}

example/setup.py

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+from setuptools import Extension, setup
+
+setup(
+    name='pyzigtest',
+    version='0.1.0',
+    python_requires='>=3.10',
+    build_zig=True,
+    ext_modules=[
+        Extension(
+            'pyzigtest',
+            sources=[
+                'pyzigtest.zig'
+            ],
+            extra_compile_args=["-DOptimize=Debug"]
+        )
+    ],
+    setup_requires=['setuptools-zig'],
+)