Struct Varargs

pub struct Varargs<'a> { /* private fields */ }

Safe interface to a list of borrowed method arguments with a convenient API for common operations with them.

Note: the impl Iterator is deprecated, Varargs itself should not be treated as a consumable iterator. Instead, use Self::as_slice().

This type can be destructured into tuples:

use gdnative::prelude::*;
use gdnative::export::Varargs;

#[derive(NativeClass)]
#[no_constructor]
struct MyClass {}

struct CalcMethod;
impl Method<MyClass> for CalcMethod {
    fn call(
        &self,
        _this: TInstance<'_, MyClass>,
        args: Varargs<'_>,
    ) -> Variant {
        // Destructure via try_into():
        let (a, b): (i64, i64) = args.try_into().expect("signature mismatch");
        let ret = a * b;
        ret.to_variant()
    }
}

Implementations

impl<'a> Varargs<'a>

pub fn len(&self) -> usize

Returns the amount of arguments left.

pub fn is_empty(&self) -> bool

pub fn read<T: FromVariant>(&mut self) -> ArgBuilder<'_, 'a, T>

Returns a builder for reading the next argument, that can be used to refine the error message on failure.

pub fn read_many<T: FromVarargs>(&mut self) -> Result<T, Vec<ArgumentError<'a>>>

Parses a structure that implements FromVarargs incrementally from the remaining arguments.

pub fn as_slice(&self) -> &'a [&'a Variant]

Returns the remaining arguments as a slice of Variants.

pub fn done(self) -> Result<(), ArgumentError<'a>>

Discard the rest of the arguments, and return an error if there is any.

Errors

If there are any excess arguments left.

pub fn check_length( &self, expected: impl Into<IndexBounds>, ) -> Result<(), VarargsError>

Check the length of arguments.

See Self::get() or Self::get_opt() for examples.

Errors

Returns an VarargsError::InvalidLength if the length of arguments is outside the specified range.

pub fn get<T: FromVariant>(&self, index: usize) -> Result<T, VarargsError>

Returns the type-converted value at the specified argument position.

Errors

Returns a VarargsError::InvalidArgumentType if the conversion fails or the argument is not set.

Examples

    args.check_length(2)?;
    let a: usize = args.get(0)?;
    let rest: i64 = args.get(1)?;

pub fn get_opt<T: FromVariant>( &self, index: usize, ) -> Result<Option<T>, VarargsError>

Returns the type-converted value at the specified argument position. Returns None if the argument is not set.

Errors

Returns a VarargsError::InvalidArgumentType if the conversion fails.

Examples

    args.check_length(1..=2)?;
    let a: usize = args.get(0)?;
    let rest: i64 = args.get_opt(1)?.unwrap_or(72);

Trait Implementations

impl<'a> Iterator for Varargs<'a>

type Item = &'a Variant

The type of the elements being iterated over.

fn next(&mut self) -> Option<Self::Item>

Advances the iterator and returns the next value.

fn next_chunk<const N: usize>( &mut self, ) -> Result<[Self::Item; N], IntoIter<Self::Item, N>>

where Self: Sized,

🔬This is a nightly-only experimental API. (iter_next_chunk)

Advances the iterator and returns an array containing the next N values.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the iterator.

fn count(self) -> usize

where Self: Sized,

Consumes the iterator, counting the number of iterations and returning it.

fn last(self) -> Option<Self::Item>

where Self: Sized,

Consumes the iterator, returning the last element.

fn advance_by(&mut self, n: usize) -> Result<(), NonZero<usize>>

🔬This is a nightly-only experimental API. (iter_advance_by)

Advances the iterator by n elements.

fn nth(&mut self, n: usize) -> Option<Self::Item>

Returns the nth element of the iterator.

fn step_by(self, step: usize) -> StepBy<Self>

where Self: Sized,

Creates an iterator starting at the same point, but stepping by the given amount at each iteration.

fn chain<U>(self, other: U) -> Chain<Self, <U as IntoIterator>::IntoIter>

where Self: Sized, U: IntoIterator<Item = Self::Item>,

Takes two iterators and creates a new iterator over both in sequence.

fn zip<U>(self, other: U) -> Zip<Self, <U as IntoIterator>::IntoIter>

where Self: Sized, U: IntoIterator,

‘Zips up’ two iterators into a single iterator of pairs.

fn intersperse(self, separator: Self::Item) -> Intersperse<Self>

where Self: Sized, Self::Item: Clone,

🔬This is a nightly-only experimental API. (iter_intersperse)

Creates a new iterator which places a copy of separator between adjacent items of the original iterator.

fn intersperse_with<G>(self, separator: G) -> IntersperseWith<Self, G>

where Self: Sized, G: FnMut() -> Self::Item,

🔬This is a nightly-only experimental API. (iter_intersperse)

Creates a new iterator which places an item generated by separator between adjacent items of the original iterator.

fn map<B, F>(self, f: F) -> Map<Self, F>

where Self: Sized, F: FnMut(Self::Item) -> B,

Takes a closure and creates an iterator which calls that closure on each element.

fn for_each<F>(self, f: F)

where Self: Sized, F: FnMut(Self::Item),

Calls a closure on each element of an iterator.

fn filter<P>(self, predicate: P) -> Filter<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator which uses a closure to determine if an element should be yielded.

fn filter_map<B, F>(self, f: F) -> FilterMap<Self, F>

where Self: Sized, F: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both filters and maps.

fn enumerate(self) -> Enumerate<Self>

where Self: Sized,

Creates an iterator which gives the current iteration count as well as the next value.

fn peekable(self) -> Peekable<Self>

where Self: Sized,

Creates an iterator which can use the peek and peek_mut methods to look at the next element of the iterator without consuming it. See their documentation for more information.

fn skip_while<P>(self, predicate: P) -> SkipWhile<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator that skips elements based on a predicate.

fn take_while<P>(self, predicate: P) -> TakeWhile<Self, P>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Creates an iterator that yields elements based on a predicate.

fn map_while<B, P>(self, predicate: P) -> MapWhile<Self, P>

where Self: Sized, P: FnMut(Self::Item) -> Option<B>,

Creates an iterator that both yields elements based on a predicate and maps.

fn skip(self, n: usize) -> Skip<Self>

where Self: Sized,

Creates an iterator that skips the first n elements.

fn take(self, n: usize) -> Take<Self>

where Self: Sized,

Creates an iterator that yields the first n elements, or fewer if the underlying iterator ends sooner.

fn scan<St, B, F>(self, initial_state: St, f: F) -> Scan<Self, St, F>

where Self: Sized, F: FnMut(&mut St, Self::Item) -> Option<B>,

An iterator adapter which, like fold, holds internal state, but unlike fold, produces a new iterator.

fn flat_map<U, F>(self, f: F) -> FlatMap<Self, U, F>

where Self: Sized, U: IntoIterator, F: FnMut(Self::Item) -> U,

Creates an iterator that works like map, but flattens nested structure.

fn map_windows<F, R, const N: usize>(self, f: F) -> MapWindows<Self, F, N>

where Self: Sized, F: FnMut(&[Self::Item; N]) -> R,

🔬This is a nightly-only experimental API. (iter_map_windows)

Calls the given function f for each contiguous window of size N over self and returns an iterator over the outputs of f. Like slice::windows(), the windows during mapping overlap as well.

fn fuse(self) -> Fuse<Self>

where Self: Sized,

Creates an iterator which ends after the first None.

fn inspect<F>(self, f: F) -> Inspect<Self, F>

where Self: Sized, F: FnMut(&Self::Item),

Does something with each element of an iterator, passing the value on.

fn by_ref(&mut self) -> &mut Self

where Self: Sized,

Creates a “by reference” adapter for this instance of Iterator.

fn collect<B>(self) -> B

where B: FromIterator<Self::Item>, Self: Sized,

Transforms an iterator into a collection.

fn collect_into<E>(self, collection: &mut E) -> &mut E

where E: Extend<Self::Item>, Self: Sized,

🔬This is a nightly-only experimental API. (iter_collect_into)

Collects all the items from an iterator into a collection.

fn partition<B, F>(self, f: F) -> (B, B)

where Self: Sized, B: Default + Extend<Self::Item>, F: FnMut(&Self::Item) -> bool,

Consumes an iterator, creating two collections from it.

fn is_partitioned<P>(self, predicate: P) -> bool

where Self: Sized, P: FnMut(Self::Item) -> bool,

🔬This is a nightly-only experimental API. (iter_is_partitioned)

Checks if the elements of this iterator are partitioned according to the given predicate, such that all those that return true precede all those that return false.

fn try_fold<B, F, R>(&mut self, init: B, f: F) -> R

where Self: Sized, F: FnMut(B, Self::Item) -> R, R: Try<Output = B>,

An iterator method that applies a function as long as it returns successfully, producing a single, final value.

fn try_for_each<F, R>(&mut self, f: F) -> R

where Self: Sized, F: FnMut(Self::Item) -> R, R: Try<Output = ()>,

An iterator method that applies a fallible function to each item in the iterator, stopping at the first error and returning that error.

fn fold<B, F>(self, init: B, f: F) -> B

where Self: Sized, F: FnMut(B, Self::Item) -> B,

Folds every element into an accumulator by applying an operation, returning the final result.

fn reduce<F>(self, f: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(Self::Item, Self::Item) -> Self::Item,

Reduces the elements to a single one, by repeatedly applying a reducing operation.

fn try_reduce<R>( &mut self, f: impl FnMut(Self::Item, Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<<R as Try>::Output>>>::TryType

where Self: Sized, R: Try<Output = Self::Item>, <R as Try>::Residual: Residual<Option<Self::Item>>,

🔬This is a nightly-only experimental API. (iterator_try_reduce)

Reduces the elements to a single one by repeatedly applying a reducing operation. If the closure returns a failure, the failure is propagated back to the caller immediately.

fn all<F>(&mut self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> bool,

Tests if every element of the iterator matches a predicate.

fn any<F>(&mut self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> bool,

Tests if any element of the iterator matches a predicate.

fn find<P>(&mut self, predicate: P) -> Option<Self::Item>

where Self: Sized, P: FnMut(&Self::Item) -> bool,

Searches for an element of an iterator that satisfies a predicate.

fn find_map<B, F>(&mut self, f: F) -> Option<B>

where Self: Sized, F: FnMut(Self::Item) -> Option<B>,

Applies function to the elements of iterator and returns the first non-none result.

fn try_find<R>( &mut self, f: impl FnMut(&Self::Item) -> R, ) -> <<R as Try>::Residual as Residual<Option<Self::Item>>>::TryType

where Self: Sized, R: Try<Output = bool>, <R as Try>::Residual: Residual<Option<Self::Item>>,

🔬This is a nightly-only experimental API. (try_find)

Applies function to the elements of iterator and returns the first true result or the first error.

fn position<P>(&mut self, predicate: P) -> Option<usize>

where Self: Sized, P: FnMut(Self::Item) -> bool,

Searches for an element in an iterator, returning its index.

fn max(self) -> Option<Self::Item>

where Self: Sized, Self::Item: Ord,

Returns the maximum element of an iterator.

fn min(self) -> Option<Self::Item>

where Self: Sized, Self::Item: Ord,

Returns the minimum element of an iterator.

fn max_by_key<B, F>(self, f: F) -> Option<Self::Item>

where B: Ord, Self: Sized, F: FnMut(&Self::Item) -> B,

Returns the element that gives the maximum value from the specified function.

fn max_by<F>(self, compare: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Ordering,

Returns the element that gives the maximum value with respect to the specified comparison function.

fn min_by_key<B, F>(self, f: F) -> Option<Self::Item>

where B: Ord, Self: Sized, F: FnMut(&Self::Item) -> B,

Returns the element that gives the minimum value from the specified function.

fn min_by<F>(self, compare: F) -> Option<Self::Item>

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> Ordering,

Returns the element that gives the minimum value with respect to the specified comparison function.

fn unzip<A, B, FromA, FromB>(self) -> (FromA, FromB)

where FromA: Default + Extend<A>, FromB: Default + Extend<B>, Self: Sized + Iterator<Item = (A, B)>,

Converts an iterator of pairs into a pair of containers.

fn copied<'a, T>(self) -> Copied<Self>

where T: 'a + Copy, Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which copies all of its elements.

fn cloned<'a, T>(self) -> Cloned<Self>

where T: 'a + Clone, Self: Sized + Iterator<Item = &'a T>,

Creates an iterator which clones all of its elements.

fn array_chunks<const N: usize>(self) -> ArrayChunks<Self, N>

where Self: Sized,

🔬This is a nightly-only experimental API. (iter_array_chunks)

Returns an iterator over N elements of the iterator at a time.

fn sum<S>(self) -> S

where Self: Sized, S: Sum<Self::Item>,

Sums the elements of an iterator.

fn product<P>(self) -> P

where Self: Sized, P: Product<Self::Item>,

Iterates over the entire iterator, multiplying all the elements

fn cmp<I>(self, other: I) -> Ordering

where I: IntoIterator<Item = Self::Item>, Self::Item: Ord, Self: Sized,

Lexicographically compares the elements of this Iterator with those of another.

fn cmp_by<I, F>(self, other: I, cmp: F) -> Ordering

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Ordering,

🔬This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn partial_cmp<I>(self, other: I) -> Option<Ordering>

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Lexicographically compares the PartialOrd elements of this Iterator with those of another. The comparison works like short-circuit evaluation, returning a result without comparing the remaining elements. As soon as an order can be determined, the evaluation stops and a result is returned.

fn partial_cmp_by<I, F>(self, other: I, partial_cmp: F) -> Option<Ordering>

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> Option<Ordering>,

🔬This is a nightly-only experimental API. (iter_order_by)

Lexicographically compares the elements of this Iterator with those of another with respect to the specified comparison function.

fn eq<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialEq<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are equal to those of another.

fn eq_by<I, F>(self, other: I, eq: F) -> bool

where Self: Sized, I: IntoIterator, F: FnMut(Self::Item, <I as IntoIterator>::Item) -> bool,

🔬This is a nightly-only experimental API. (iter_order_by)

Determines if the elements of this Iterator are equal to those of another with respect to the specified equality function.

fn ne<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialEq<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are not equal to those of another.

fn lt<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically less than those of another.

fn le<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically less or equal to those of another.

fn gt<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically greater than those of another.

fn ge<I>(self, other: I) -> bool

where I: IntoIterator, Self::Item: PartialOrd<<I as IntoIterator>::Item>, Self: Sized,

Determines if the elements of this Iterator are lexicographically greater than or equal to those of another.

fn is_sorted(self) -> bool

where Self: Sized, Self::Item: PartialOrd,

Checks if the elements of this iterator are sorted.

fn is_sorted_by<F>(self, compare: F) -> bool

where Self: Sized, F: FnMut(&Self::Item, &Self::Item) -> bool,

Checks if the elements of this iterator are sorted using the given comparator function.

fn is_sorted_by_key<F, K>(self, f: F) -> bool

where Self: Sized, F: FnMut(Self::Item) -> K, K: PartialOrd,

Checks if the elements of this iterator are sorted using the given key extraction function.

impl<'a> TryFrom<Varargs<'a>> for ()

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant> TryFrom<Varargs<'a>> for (A,)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant> TryFrom<Varargs<'a>> for (A, B)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant> TryFrom<Varargs<'a>> for (A, B, C)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant, E: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D, E)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant, E: FromVariant, F: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D, E, F)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant, E: FromVariant, F: FromVariant, G: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D, E, F, G)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant, E: FromVariant, F: FromVariant, G: FromVariant, H: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D, E, F, G, H)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant, E: FromVariant, F: FromVariant, G: FromVariant, H: FromVariant, I: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D, E, F, G, H, I)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant, E: FromVariant, F: FromVariant, G: FromVariant, H: FromVariant, I: FromVariant, J: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D, E, F, G, H, I, J)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant, E: FromVariant, F: FromVariant, G: FromVariant, H: FromVariant, I: FromVariant, J: FromVariant, K: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D, E, F, G, H, I, J, K)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.

impl<'a, A: FromVariant, B: FromVariant, C: FromVariant, D: FromVariant, E: FromVariant, F: FromVariant, G: FromVariant, H: FromVariant, I: FromVariant, J: FromVariant, K: FromVariant, L: FromVariant> TryFrom<Varargs<'a>> for (A, B, C, D, E, F, G, H, I, J, K, L)

type Error = VarargsError

The type returned in the event of a conversion error.

fn try_from(args: Varargs<'a>) -> Result<Self, Self::Error>

Performs the conversion.