godot_core/meta/
param_tuple.rs

1/*
2 * Copyright (c) godot-rust; Bromeon and contributors.
3 * This Source Code Form is subject to the terms of the Mozilla Public
4 * License, v. 2.0. If a copy of the MPL was not distributed with this
5 * file, You can obtain one at https://mozilla.org/MPL/2.0/.
6 */
7
8use godot_ffi as sys;
9
10use super::{CallContext, CallResult, PropertyInfo};
11use crate::builtin::Variant;
12
13mod impls;
14
15/// Represents a parameter list as Rust tuple where each tuple element is one parameter.
16///
17/// This trait only contains metadata for the parameter list, the actual functionality is contained in [`InParamTuple`] and
18/// [`OutParamTuple`].
19pub trait ParamTuple: Sized {
20    /// The number of elements in this parameter list.
21    const LEN: usize;
22
23    /// The param info of the parameter at index `index`.
24    #[doc(hidden)]
25    fn param_info(
26        index: usize,
27        param_name: &str,
28    ) -> Option<crate::registry::method::MethodParamOrReturnInfo>;
29
30    /// The property info of the parameter at index `index`.
31    fn property_info(index: usize, param_name: &str) -> Option<PropertyInfo> {
32        Self::param_info(index, param_name).map(|param| param.info)
33    }
34
35    /// Return a string representing the arguments.
36    fn format_args(&self) -> String;
37}
38
39/// Represents a parameter list that is received from some external location (usually Godot).
40///
41/// As an example, this would be used for user-defined functions that will be called from Godot, however this is _not_ used when
42/// calling a Godot function from Rust code.
43pub trait InParamTuple: ParamTuple {
44    /// Converts `args_ptr` to `Self` by first going through [`Variant`].
45    ///
46    /// # Safety
47    ///
48    /// - `args_ptr` must be a pointer to an array of length [`Self::LEN`](ParamTuple::LEN)
49    /// - Each element of `args_ptr` must be reborrowable as a `&Variant` with a lifetime that lasts for the duration of the call.
50    #[doc(hidden)] // Hidden since v0.3.2.
51    unsafe fn from_varcall_args(
52        args_ptr: *const sys::GDExtensionConstVariantPtr,
53        call_ctx: &CallContext,
54    ) -> CallResult<Self>;
55
56    /// Converts `args_ptr` to `Self` directly.
57    ///
58    /// # Safety
59    ///
60    /// - `args_ptr` must be a pointer to a valid array of length [`Self::LEN`](ParamTuple::LEN)
61    /// - each element of `args_ptr` must be of the same type as each element of `Self`
62    #[doc(hidden)] // Hidden since v0.3.2.
63    unsafe fn from_ptrcall_args(
64        args_ptr: *const sys::GDExtensionConstTypePtr,
65        call_type: sys::PtrcallType,
66        call_ctx: &CallContext,
67    ) -> Self;
68
69    /// Converts `array` to `Self` by calling [`from_variant`](crate::meta::FromGodot::from_variant) on each argument.
70    fn from_variant_array(array: &[&Variant]) -> Self;
71}
72
73/// Represents a parameter list that is used to call some external code.
74///
75/// As an example, this would be used to call Godot functions through FFI, however this is _not_ used when Godot calls a user-defined
76/// function.
77pub trait OutParamTuple: ParamTuple {
78    /// Call `f` on the tuple `self` by first converting `self` to an array of [`Variant`]s.
79    fn with_variants<F, R>(self, f: F) -> R
80    where
81        F: FnOnce(&[Variant]) -> R;
82
83    /// Call `f` on the tuple `self` by first converting `self` to an array of [`Variant`] pointers.
84    #[doc(hidden)] // Hidden since v0.3.2.
85    fn with_variant_pointers<F, R>(self, f: F) -> R
86    where
87        F: FnOnce(&[sys::GDExtensionConstVariantPtr]) -> R;
88
89    /// Call `f` on the tuple `self` by first converting `self` to an array of Godot type pointers.
90    #[doc(hidden)] // Hidden since v0.3.2.
91    fn with_type_pointers<F, R>(self, f: F) -> R
92    where
93        F: FnOnce(&[sys::GDExtensionConstTypePtr]) -> R;
94
95    /// Converts `array` to `Self` by calling [`to_variant`](crate::meta::ToGodot::to_variant) on each argument.
96    fn to_variant_array(&self) -> Vec<Variant>;
97}
godot_core/meta/param_tuple.rs

godot_core/meta/
param_tuple.rs
