Add more to types

content/types/distinct.md

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+---
+title: Distinct Types
+---
+# Distinct Types
+
+Distinct types are like other type aliases, but they provide type safety so that it is impossible to coerce a distinct type into its base type without explicit conversion.
+
+``` nimrod
+type
+  Dollars* = distinct float
+
+var a = 20.Dollars
+a = 25  # Doesn't compile
+a = 25.Dollars  # Works fine
+```
+
+However, when using distinct types, none of the base type's procedures follow the type. To solve this, it is possible to create lots of procedures that basically act as a thin wrapper for the underlying types, or the `{.borrow.}` pragma can be used to automate generation of procedures.
+
+``` nimrod
+proc `*` *(a, b: Dollars): Dollars {.borrow.}
+proc `+` *(a, b: Dollars): Dollars {.borrow.}
+a = 20.Dollars * 20.Dollars
+```
+<!--- XXX Uug, {.borrow: `.`.} -->