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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/group_map.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/group_map.rs')
-rw-r--r--vendor/itertools-0.11.0/src/group_map.rs32
1 files changed, 32 insertions, 0 deletions
diff --git a/vendor/itertools-0.11.0/src/group_map.rs b/vendor/itertools-0.11.0/src/group_map.rs
new file mode 100644
index 000000000..a2d0ebb2a
--- /dev/null
+++ b/vendor/itertools-0.11.0/src/group_map.rs
@@ -0,0 +1,32 @@
+#![cfg(feature = "use_std")]
+
+use std::collections::HashMap;
+use std::hash::Hash;
+use std::iter::Iterator;
+
+/// Return a `HashMap` of keys mapped to a list of their corresponding values.
+///
+/// See [`.into_group_map()`](crate::Itertools::into_group_map)
+/// for more information.
+pub fn into_group_map<I, K, V>(iter: I) -> HashMap<K, Vec<V>>
+ where I: Iterator<Item=(K, V)>,
+ K: Hash + Eq,
+{
+ let mut lookup = HashMap::new();
+
+ iter.for_each(|(key, val)| {
+ lookup.entry(key).or_insert_with(Vec::new).push(val);
+ });
+
+ lookup
+}
+
+pub fn into_group_map_by<I, K, V>(iter: I, f: impl Fn(&V) -> K) -> HashMap<K, Vec<V>>
+ where
+ I: Iterator<Item=V>,
+ K: Hash + Eq,
+{
+ into_group_map(
+ iter.map(|v| (f(&v), v))
+ )
+}