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+# 1.03 Str type.
+
+Read-only string of bytes. Use `Str.size` to get the size in bytes
+of the string (without NUL terminator). All KC3 strings are bound-
+checked according to their size and are NUL terminated.
+
+## 1.03.1 String litterals and interpolation
+
+A string litteral starts with either double quotes `"` or
+Inside of a string litteral you can use the `#{expr}` to evaluate
+expr to a Str inside of the litteral. The string litteral is then
+parsed as a Call to KC3.str .
+
+## 1.03.2 Examples
+
+```elixir
+ikc3> "123"
+"123"
+ikc3> type("123")
+Str
+ikc3> b = 2
+2
+ikc3> "1#{b}3"
+"123"
+ikc3> type("1#{b}3")
+Str
+ikc3> quote "1#{b}3"
+"1#{b}3"
+ikc3> type(quote "1#{b}3")
+Call
+ikc3> type(quote quote "1#{b}3")
+Quote
+```