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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-06-19 09:26:03 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-06-19 09:26:03 +0000
commit9918693037dce8aa4bb6f08741b6812923486c18 (patch)
tree21d2b40bec7e6a7ea664acee056eb3d08e15a1cf /vendor/itertools-0.11.0/src/process_results_impl.rs
parentReleasing progress-linux version 1.75.0+dfsg1-5~progress7.99u1. (diff)
downloadrustc-9918693037dce8aa4bb6f08741b6812923486c18.tar.xz
rustc-9918693037dce8aa4bb6f08741b6812923486c18.zip
Merging upstream version 1.76.0+dfsg1.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'vendor/itertools-0.11.0/src/process_results_impl.rs')
-rw-r--r--vendor/itertools-0.11.0/src/process_results_impl.rs68
1 files changed, 68 insertions, 0 deletions
diff --git a/vendor/itertools-0.11.0/src/process_results_impl.rs b/vendor/itertools-0.11.0/src/process_results_impl.rs
new file mode 100644
index 000000000..713db4551
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+++ b/vendor/itertools-0.11.0/src/process_results_impl.rs
@@ -0,0 +1,68 @@
+#[cfg(doc)]
+use crate::Itertools;
+
+/// An iterator that produces only the `T` values as long as the
+/// inner iterator produces `Ok(T)`.
+///
+/// Used by [`process_results`](crate::process_results), see its docs
+/// for more information.
+#[must_use = "iterator adaptors are lazy and do nothing unless consumed"]
+#[derive(Debug)]
+pub struct ProcessResults<'a, I, E: 'a> {
+ error: &'a mut Result<(), E>,
+ iter: I,
+}
+
+impl<'a, I, T, E> Iterator for ProcessResults<'a, I, E>
+ where I: Iterator<Item = Result<T, E>>
+{
+ type Item = T;
+
+ fn next(&mut self) -> Option<Self::Item> {
+ match self.iter.next() {
+ Some(Ok(x)) => Some(x),
+ Some(Err(e)) => {
+ *self.error = Err(e);
+ None
+ }
+ None => None,
+ }
+ }
+
+ fn size_hint(&self) -> (usize, Option<usize>) {
+ (0, self.iter.size_hint().1)
+ }
+
+ fn fold<B, F>(mut self, init: B, mut f: F) -> B
+ where
+ Self: Sized,
+ F: FnMut(B, Self::Item) -> B,
+ {
+ let error = self.error;
+ self.iter
+ .try_fold(init, |acc, opt| match opt {
+ Ok(x) => Ok(f(acc, x)),
+ Err(e) => {
+ *error = Err(e);
+ Err(acc)
+ }
+ })
+ .unwrap_or_else(|e| e)
+ }
+}
+
+/// “Lift” a function of the values of an iterator so that it can process
+/// an iterator of `Result` values instead.
+///
+/// [`IntoIterator`] enabled version of [`Itertools::process_results`].
+pub fn process_results<I, F, T, E, R>(iterable: I, processor: F) -> Result<R, E>
+ where I: IntoIterator<Item = Result<T, E>>,
+ F: FnOnce(ProcessResults<I::IntoIter, E>) -> R
+{
+ let iter = iterable.into_iter();
+ let mut error = Ok(());
+
+ let result = processor(ProcessResults { error: &mut error, iter });
+
+ error.map(|_| result)
+}