affn-derive 0.7.1

Derive macros for affn: ReferenceFrame and ReferenceCenter
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150

//! # affn-derive
//!
//! Derive macros for the `affn` crate, providing `#[derive(ReferenceFrame)]`
//! and `#[derive(ReferenceCenter)]` for convenient frame and center definitions.
//!
//! ## Usage
//!
//! These derives are re-exported from `affn`, so you typically use them as:
//!
//! ```rust,ignore
//! use affn::{ReferenceFrame, ReferenceCenter};
//!
//! #[derive(Debug, Copy, Clone, ReferenceFrame)]
//! struct MyFrame;
//!
//! #[derive(Debug, Copy, Clone, ReferenceCenter)]
//! struct MyCenter;
//! ```
//!
//! ## Attributes
//!
//! ### `#[derive(ReferenceFrame)]`
//!
//! - `#[frame(name = "CustomName")]` - Override the frame name (defaults to struct name)
//! - `#[frame(polar = "dec", azimuth = "ra")]` - Also implement `SphericalNaming` with custom names
//! - `#[frame(distance = "altitude")]` - Override distance name (defaults to "distance")
//! - `#[frame(inherent)]` - Generate inherent methods on `Direction<F>` and `Position<C,F,U>`.
//!   Only valid when the frame is defined in the same crate as `Direction`/`Position`.
//! - `#[frame(ellipsoid = "Wgs84")]` - Also implement `HasEllipsoid` for the frame.
//!
//! ### `#[derive(ReferenceCenter)]`
//!
//! - `#[center(name = "CustomName")]` - Override the center name (defaults to struct name)
//! - `#[center(params = MyParamsType)]` - Specify the `Params` associated type (defaults to `()`)
//! - `#[center(affine = false)]` - Skip implementing `AffineCenter` marker trait

use proc_macro::TokenStream;
use syn::{parse_macro_input, DeriveInput};

mod center;
mod frame;

// =============================================================================
// ReferenceFrame derive
// =============================================================================

/// Derive macro for implementing [`ReferenceFrame`](affn::frames::ReferenceFrame).
///
/// # Example
///
/// ```rust,ignore
/// use affn::ReferenceFrame;
///
/// #[derive(Debug, Copy, Clone, ReferenceFrame)]
/// struct ICRS;
///
/// assert_eq!(ICRS::frame_name(), "ICRS");
/// ```
///
/// ## Custom Name
///
/// ```rust,ignore
/// #[derive(Debug, Copy, Clone, ReferenceFrame)]
/// #[frame(name = "International Celestial Reference System")]
/// struct ICRS;
///
/// assert_eq!(ICRS::frame_name(), "International Celestial Reference System");
/// ```
///
/// ## SphericalNaming
///
/// When `polar` and `azimuth` attributes are provided, the macro also implements
/// [`SphericalNaming`](affn::frames::SphericalNaming):
///
/// ```rust,ignore
/// #[derive(Debug, Copy, Clone, ReferenceFrame)]
/// #[frame(polar = "dec", azimuth = "ra")]
/// struct ICRS;
///
/// assert_eq!(ICRS::polar_name(), "dec");
/// assert_eq!(ICRS::azimuth_name(), "ra");
/// assert_eq!(ICRS::distance_name(), "distance"); // default
/// ```
///
/// With custom distance name:
///
/// ```rust,ignore
/// #[derive(Debug, Copy, Clone, ReferenceFrame)]
/// #[frame(polar = "lat", azimuth = "lon", distance = "altitude")]
/// struct ITRF;
/// ```
#[proc_macro_derive(ReferenceFrame, attributes(frame))]
pub fn derive_reference_frame(input: TokenStream) -> TokenStream {
    let input = parse_macro_input!(input as DeriveInput);
    match frame::derive_reference_frame_impl(input) {
        Ok(tokens) => tokens.into(),
        Err(err) => err.to_compile_error().into(),
    }
}

// =============================================================================
// ReferenceCenter derive
// =============================================================================

/// Derive macro for implementing [`ReferenceCenter`](affn::centers::ReferenceCenter).
///
/// By default, this also implements [`AffineCenter`](affn::centers::AffineCenter).
///
/// # Example
///
/// ```rust,ignore
/// use affn::ReferenceCenter;
///
/// #[derive(Debug, Copy, Clone, ReferenceCenter)]
/// struct Heliocentric;
///
/// assert_eq!(Heliocentric::center_name(), "Heliocentric");
/// ```
///
/// ## Custom Parameters
///
/// ```rust,ignore
/// use affn::ReferenceCenter;
///
/// #[derive(Clone, Debug, Default, PartialEq)]
/// struct ObserverLocation {
///     lat: f64,
///     lon: f64,
/// }
///
/// #[derive(Debug, Copy, Clone, ReferenceCenter)]
/// #[center(params = ObserverLocation)]
/// struct Topocentric;
/// ```
///
/// ## Skip AffineCenter
///
/// ```rust,ignore
/// #[derive(Debug, Copy, Clone, ReferenceCenter)]
/// #[center(affine = false)]
/// struct NonAffineCenter;
/// ```
#[proc_macro_derive(ReferenceCenter, attributes(center))]
pub fn derive_reference_center(input: TokenStream) -> TokenStream {
    let input = parse_macro_input!(input as DeriveInput);
    match center::derive_reference_center_impl(input) {
        Ok(tokens) => tokens.into(),
        Err(err) => err.to_compile_error().into(),
    }
}