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content/types/range.md

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+---
+title: Range Types
+---
+# Range Types
+
+Range types that guarantee a value will always be within a given range also exist. Whenever possible, out-of-bounds values will fail at compile-time, otherwise they will fail at run-time.
+
+``` nimrod
+type
+  TwoDigits* = range[10..99]
+
+let a = 2
+var b: TwoDigits = 99 + a  # Fails at run-time
+let c: TwoDigits = 100  # Fails at compile-time
+```
+
+Also note that range types also work on any other ordinal type, so a range over an enum is also valid:
+
+``` nimrod
+type
+  MyEnum = enum
+    A, B, C, D, E
+  BToD = range[B..D]
+
+let value: BToD = C
+```