vault backup: 2025-08-04 08:46:49

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diff --git a/A scope block is an expression.md b/A scope block is an expression.md
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+[[Rust]]
+
+An expression evaluates to a value. In Rust that can also mean a scope block as follows:
+```rust
+fn main() {
+    let y = {
+        let x = 3;
+        x + 1
+    };
+
+    println!("The value of y is: {y}");
+}
+```
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diff --git a/Adding a semicolon to the end of a line turns it into a statement.md b/Adding a semicolon to the end of a line turns it into a statement.md
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+[[Rust]]
+[[How to return from a function]]
+
+Any line that ends with a semicolon is a statement, thus it returns no value. A line ending without a semicolon is an expression that returns a value.
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diff --git a/How to return from a function.md b/How to return from a function.md
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+[[Rust]]
+[[Adding a semicolon to the end of a line turns it into a statement]]
+
+In Rust we can return from a function with simply an expression at the end of the scope.
+
+The `return` keyword is mostly used for returning early.
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diff --git a/If is not a statement but an expression.md b/If is not a statement but an expression.md
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+++ b/If is not a statement but an expression.md
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+[[Rust]]
+[[Statement vs expression]]
+
+An if statement is not a statement in rust! It is an expression! Thus we can use it in an assignment for example.
diff --git a/It is not possible to do a chain assignment.md b/It is not possible to do a chain assignment.md
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+++ b/It is not possible to do a chain assignment.md
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+[[Rust]]
+[[Statement vs expression]]
+
+Because a statement does not have a return value it is not possible to do
+`let x = (let y = 6)`
+
+Also `let x = y = 6;` is not possible because now `y` is never defined.
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diff --git a/Loop labels.md b/Loop labels.md
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+++ b/Loop labels.md
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+[[Rust]]
+[[Returning values from loops]]
+
+In nested loops we can use labels to determine which one to break from:
+```rust
+fn main() {
+    let mut count = 0;
+    'counting_up: loop {
+        println!("count = {count}");
+        let mut remaining = 10;
+
+        loop {
+            println!("remaining = {remaining}");
+            if remaining == 9 {
+                break;
+            }
+            if count == 2 {
+                break 'counting_up;
+            }
+            remaining -= 1;
+        }
+
+        count += 1;
+    }
+    println!("End count = {count}");
+}
+```
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diff --git a/Loop over an array with for-in.md b/Loop over an array with for-in.md
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+++ b/Loop over an array with for-in.md
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+[[Rust]]
+
+```rust
+for number in (1..4).rev() {
+	println!("reversed: {number}");
+}
+```
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diff --git a/Returning values from loops.md b/Returning values from loops.md
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+++ b/Returning values from loops.md
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+[[Rust]]
+[[A scope block is an expression]]
+[[Loop labels]]
+
+
+A loop can return values, it is an expression. Thus it can be used in an assignment as well.
+It is possible to `return ` but that would exit the function, instead we can also `break expression;` and return a value just from the loop by breaking it with a value (as we would normally write a `return`).
+
+```rust
+fn main() {
+    let mut counter = 0;
+
+    let result = loop {
+        counter += 1;
+
+        if counter == 10 {
+            break counter * 2;
+        }
+    };
+
+    println!("The result is {result}");
+}
+```
diff --git a/Rust.md b/Rust.md
index 1733c8f..39825ee 100644
--- a/Rust.md
+++ b/Rust.md
@@ -15,3 +15,11 @@
 [[Primitive values such as the array are allocated on the stack]]
 [[Arrays are useful when you know the length will not change]]
 [[Array notation]]
+[[A scope block is an expression]]
+[[Adding a semicolon to the end of a line turns it into a statement]]
+[[How to return from a function]]
+[[Statement vs expression]]
+[[There is no truthiness]]
+[[If is not a statement but an expression]]
+[[Returning values from loops]]
+[[Loop over an array with for-in]]
diff --git a/Statement vs expression.md b/Statement vs expression.md
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+++ b/Statement vs expression.md
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+[[Rust]]
+[[A scope block is an expression]]
+[[How to return from a function]]
+[[Adding a semicolon to the end of a line turns it into a statement]]
+[[It is not possible to do a chain assignment]]
+[[An empty tuple is called a unit]]
+
+An expression returns something, ie `1 + 2` returns `3`.
+A statement on the other hand does not return anything: as assignment is a statement. It equals to the unit!
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diff --git a/There is no truthiness.md b/There is no truthiness.md
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+[[Rust]]
+
+It does not work to write something like:
+```rust
+let number = 3;
+
+if number {
+// do something
+}
+```
+like in other languages
+
+Rust expects only a `bool` in an if statement, so we'd need to compare it.
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