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_archive/rhai_engine/rhaibook/language/switch-expression.md

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+Switch Expression
+=================
+
+{{#include ../links.md}}
+
+Like [`if`], [`switch`] also works as an _expression_.
+
+```admonish tip.small "Tip"
+
+This means that a [`switch`] expression can appear anywhere a regular expression can,
+e.g. as [function] call arguments.
+```
+
+~~~admonish tip.small "Tip: Disable `switch` expressions"
+
+[`switch`] expressions can be disabled via [`Engine::set_allow_switch_expression`][options].
+~~~
+
+```js
+let x = switch foo { 1 => true, _ => false };
+
+func(switch foo {
+    "hello" => 42,
+    "world" => 123,
+    _ => 0
+});
+
+// The above is somewhat equivalent to:
+
+let x = if foo == 1 { true } else { false };
+
+if foo == "hello" {
+    func(42);
+} else if foo == "world" {
+    func(123);
+} else {
+    func(0);
+}
+```