tried out obsidian, started ch 6.2

Variables.md

@@ -0,0 +1,32 @@
+# Variables
+- Are Immutable by default
+- can be inferred but sometimes needs explicit typing
+
+```rust
+    let foo = 5;
+```
+- Need to add mut keyword to enable rewriting, generally avoid unless actually used
+
+```rust
+    let mut bar = 6;
+```
+
+# SHADOWING
+
+#### Cannot have mutable shadows
+
+allows for reuse of namespace instead of spaces_str and spaces_num
+```rust
+    let spaces = " _ _ ";
+    let spaces = spaces.len();
+    // will output 5 instead of " _ _ " beacuse that is how long it is
+    // the shadow of spaces (first) wont be printed until the overshadow of spaces goes out of scope
+    println!("{spaces}"); // output: 5
+```
+
+not allowed shadow
+```rust
+    let mut spaces = " _ _ ";
+    spaces = spaces.len();
+```
+cannot change type of variable once declared