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Also, variable shadowing is allowed.
>fn main() {
>let shadowed_binding = 1;
>{
>println!("before being shadowed: {}", shadowed_binding);
>// This binding *shadows* the outer one
>let shadowed_binding = "abc";
>println!("shadowed in inner block: {}", shadowed_binding);
>}
>println!("outside inner block: {}", shadowed_binding);
>// This binding *shadows* the previous binding
>let shadowed_binding = 2;
>println!("shadowed in outer block: {}", shadowed_binding);
>}
>הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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It's possible to declare variable bindings first, and initialize them later. However, this form is seldom used, as it may lead to the use of uninitialized variables.
>fn main() {
>// Declare a variable binding
>let a_binding;
>{
>let x = 2;
>// Initialize the binding
>a_binding = x * x;
>}
>println!("a binding: {}", a_binding);
>let another_binding;
>// Error! Use of uninitialized binding
>println!("another binding: {}", another_binding);
>// FIXME ^ Comment out this line
>another_binding = 1;
>println!("another binding: {}", another_binding);
>}
>הההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההההה
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The compiler forbids use of uninitialized variables, as this would lead to undefined behavior.
