From c2b0a03a46ddb1aacd901b71d036656f5ba3c67f Mon Sep 17 00:00:00 2001
From: ivanjermakov <ivanjermakov1@gmail.com>
Date: Tue, 9 Apr 2024 22:16:38 +0200
Subject: [PATCH] Std: `Iter::takeWhile`

---
 src/std/iter/mod.no       |  1 +
 src/std/iter/takeWhile.no | 32 ++++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+)
 create mode 100644 src/std/iter/takeWhile.no

diff --git a/src/std/iter/mod.no b/src/std/iter/mod.no
index ca1a4a09..d6bf7cc7 100644
--- a/src/std/iter/mod.no
+++ b/src/std/iter/mod.no
@@ -2,6 +2,7 @@ pub use std::iter::{
     intersperseIter::{ IntersperseIter, IntersperseAdapter },
     mapIter::{ MapIter, MapAdapter },
     peekable::{ PeekableIter, PeekableAdapter },
+    takeWhile::{ TakeWhileIter, TakeWhileAdapter },
 }
 
 pub trait Iterable<T> {
diff --git a/src/std/iter/takeWhile.no b/src/std/iter/takeWhile.no
new file mode 100644
index 00000000..7731cd4d
--- /dev/null
+++ b/src/std/iter/takeWhile.no
@@ -0,0 +1,32 @@
+pub type TakeWhileIter<T>(
+    iter: Iter<T>,
+    f: |T|: Bool,
+    done: Bool
+)
+
+impl <T> Iter<T> for TakeWhileIter<T> {
+    fn next(self): Option<T> {
+        if self.done { return None() }
+        match self.iter.next() {
+            Some(value) {
+                if (self.f)(value).not() {
+                    self.done = true
+                    return None()
+                }
+                Some(value)
+            }
+            _ { None() }
+        }
+    }
+}
+
+pub trait TakeWhileAdapter<T> {
+    fn takeWhile(self, f: |T|: Bool): Iter<T>
+}
+
+impl <T> TakeWhileAdapter<T> for Iter<T> {
+    fn takeWhile(self, f: |T|: Bool): Iter<T> {
+        TakeWhileIter(iter: self, f, false)
+    }
+}
+