mond 0.1.0

A Rust Lua 5.3
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

// The MIT License (MIT)
//
// Copyright (c) 2016 J.C. Moyer
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.

extern crate libc;
extern crate mond;

use mond::ffi::lua_State;
use mond::{Function, State};
use libc::c_int;

struct Point2D {
    // using i64 for convenience since lua defaults to 64 bit integers
    x: i64,
    y: i64,
}

impl Point2D {
    fn new(x: i64, y: i64) -> Point2D {
        Point2D { x: x, y: y }
    }

    #[allow(non_snake_case)]
    unsafe extern "C" fn lua_new(L: *mut lua_State) -> c_int {
        let mut state = State::from_ptr(L);
        // takes two optional integer parameters
        let x = state.opt_integer(1, 0);
        let y = state.opt_integer(2, 0);
        // construct new userdata in lua space and initialize it
        *state.new_userdata_typed::<Point2D>() = Point2D::new(x, y);
        // set the userdata's metatable so we can call methods on it
        state.set_metatable_from_registry("Point2D");
        // return the userdata on top of the stack
        1
    }

    #[allow(non_snake_case)]
    unsafe extern "C" fn lua_x(L: *mut lua_State) -> c_int {
        let mut state = State::from_ptr(L);
        let point = state.check_userdata(1, "Point2D") as *mut Point2D;
        state.push_integer((*point).x);
        1
    }

    #[allow(non_snake_case)]
    unsafe extern "C" fn lua_y(L: *mut lua_State) -> c_int {
        let mut state = State::from_ptr(L);
        let point = state.check_userdata(1, "Point2D") as *mut Point2D;
        state.push_integer((*point).y);
        1
    }
}

const POINT2D_LIB: [(&str, Function); 3] = [
    ("new", Some(Point2D::lua_new)),
    ("x", Some(Point2D::lua_x)),
    ("y", Some(Point2D::lua_y)),
];

fn main() {
    let mut state = mond::State::new();

    state.open_libs();

    // make a Point2D table globally available to the lua state and register
    // our functions there:
    state.new_table();
    state.set_fns(&POINT2D_LIB, 0);
    // copy reference to Point2D table so we can keep the original reference on
    // the stack for later
    state.push_value(-1);
    state.set_global("Point2D");

    // create a metatable for Point2D in the lua registry that refers to the
    // global Point2D table:
    state.new_metatable("Point2D");
    // copy reference to Point2D table
    state.push_value(-2);
    // Point2Dmetatable.__index = Point2D
    state.set_field(-2, "__index");

    // pop metatable and Point2D table from the stack
    state.pop(2);

    // try it out:
    assert!(!state
        .do_string(
            "local p = Point2D.new(12, 34)
                   print(p:x(), p:y())"
        )
        .is_err());
}