Testing capturing resutls

capresulttest/Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 3
+
+[[package]]
+name = "capresulttest"
+version = "0.1.0"

capresulttest/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "capresulttest"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

capresulttest/README.md

@@ -0,0 +1,5 @@
+# CapResultTest
+
+It is known that a `.collect()` in which the `Item` is a `Result` will stop
+processing as soon as it finds an `Err`. But what if we capture this before
+`.collect()`?

capresulttest/src/main.rs

@@ -0,0 +1,31 @@
+fn main() {
+    let evens = [2, 2, 2, 2, 2];
+    let res = evens
+        .iter()
+        .map(|v| {
+            if v % 2 == 0 {
+                Ok(v.to_string())
+            } else {
+                Err("No".to_string())
+            }
+        })
+        .collect::<Result<Vec<String>, String>>();
+    println!("Evens: {:?}", res);
+
+    let not_evens = [2, 2, 2, 2, 1, 2];
+    let res = not_evens
+        .iter()
+        .map(|v| {
+            if v % 2 == 0 {
+                Ok(v.to_string())
+            } else {
+                Err("No".to_string())
+            }
+        })
+        .map(|res| match res {
+            Ok(v) => v,
+            Err(e) => e,
+        })
+        .collect::<Vec<String>>();
+    println!("Not evens: {:?}", res);
+}