# Zigler
Library test status:
Dependent package test status:
## Installation
Zigler is [available in Hex](https://hex.pm/zigler), and the package can be installed
by adding `zigler` to your list of dependencies in `mix.exs`:
```elixir
def deps do
[
{:zigler, "~> 0.1.3", runtime: false}
]
end
```
Documentation
be found at [https://hexdocs.pm/zigler](https://hexdocs.pm/zigler).
once you have this dependency, you should cache the zig build tools by running the following:
`mix zigler.get_zig latest`
## Currently supported platforms
- Linux
- FreeBSD (tested, but not subjected to CI)
- MacOS (I believe it works but is still offically untested)
## Zig Nifs made easy
Wouldn't it be nice if you could make NIFs as easily as you can use the `asm`
keyword in C?
This is now possible, using the magic of Zig.
```elixir
defmodule ExampleZig do
use Zigler, app: :my_app
~Z"""
/// nif: example_fun/2
fn example_fun(value1: f64, value2: f64) bool {
return value1 > value2;
}
"""
end
iex> ExampleZig.example_fun(0.1, 0.4)
false
iex> ExampleZig.example_fun(0.8, -0.8)
true
```
Zigler will do automatic type marshalling between Elixir code and Zig code.
It will also convert trickier types into types you care about, for example:
```elixir
defmodule ZigCollections do
use Zigler, app: :my_app
~Z"""
/// nif: string_count/1
fn string_count(string: []u8) i64 {
return @intCast(i64, string.len);
}
/// nif: list_sum/1
fn list_sum(array: []f64) f64 {
var sum: f64 = 0.0;
for(array) | item | {
sum += item;
}
return sum;
}
"""
end
iex> ZigCollections.string_count("hello zig")
9
iex> ZigCollections.list_sum([1.0, 2.0, 3.0])
6.0
```
Memory allocation with zigler is easy! A standard BEAM allocator is provided for you,
so any zig code you import will play nice with the BEAM.
```elixir
defmodule Allocations do
use Zigler, app: :my_app
~Z"""
/// nif: double_atom/1
fn double_atom(env: beam.env, string: []u8) beam.atom {
var double_string = beam.allocator.alloc(u8, string.len * 2) catch {
return beam.throw_enomem(env);
};
defer beam.allocator.free(double_string);
for (string) | char, i | {
double_string[i] = char;
double_string[i + string.len] = char;
}
return beam.make_atom(env, double_string);
}
"""
end
iex> Allocations.double_atom("foo")
:foofoo
```
It is a goal for Zigler to make using *it* to bind C libraries easier
than using C to bind C libraries. Here is an example:
```elixir
defmodule BlasDynamic do
use Zigler,
app: :zigler,
libs: ["/usr/lib/x86_64-linux-gnu/blas/libblas.so"],
include: ["/usr/include/x86_64-linux-gnu"]
~Z"""
const blas = @cImport({
@cInclude("cblas.h");
});
/// nif: blas_axpy/3
fn blas_axpy(env: beam.env, a: f64, x: []f64, y: []f64) beam.term {
if (x.len != y.len) {
return beam.throw_function_clause_error(env);
}
blas.cblas_daxpy(@intCast(c_int, x.len), a, &x[0], 1, &y[0], 1);
return beam.make_f64_list(env, y) catch {
return beam.throw_function_clause_error(env);
};
}
"""
end
test "we can use dynamically-linked blas" do
# returns aX+Y
assert [11.0, 18.0] == BlasDynamic.blas_axpy(3.0, [2.0, 4.0], [5.0, 6.0])
end
```
Zigler even has support for zig docstrings.
```elixir
defmodule AllTheDocs do
use Zigler, app: :zigler
~Z"""
/// a zero-arity function which returns 47.
/// nif: zero_arity/0
fn zeroarity() i64 {
return 47;
}
"""
end
iex> h AllTheDocs.zeroarity
def zeroarity()
a zero-arity function which returns 47.
```
