fn-ptr 0.1.0

A crate providing a function pointer trait.
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# fn-ptr

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A small Rust crate that exposes a `FunctionPtr` trait that is implemented for all function pointer types up to arity 12, for multiple calling conventions (ABIs). The trait looks like this:

```rust
pub trait FunctionPtr {
    const ARITY: usize;
    const SAFE: bool;
    const EXTERN: bool;
    const ABI: Abi;

    type Args;
    type Output;
}
```

**Usage**

```rust
fn print_info<F: fn_ptr::FunctionPtr>() {
    println!("arity = {}", F::ARITY);
    println!("safe = {}", F::SAFE);
    println!("extern = {}", F::EXTERN);
    println!("ABI = {:?}", F::ABI);
}

fn main() {
    print_info::<fn(i32) -> i32>();
    // Example output (typical):
    // arity = 1
    // safe = true
    // extern = false
    // ABI = Rust
    // example(10) = 11
}
```