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+## Code Generation for Standard Library
+
+Some of the code in the standard library is created by code generation based on templates.
+For example, many Array methods need to be implemented separately for Array<T>, ByteArray, ShortArray, IntArray, etc.
+
+To run the code generator from a kotlin checkout
+
+    cd libraries/tools/kotlin-stdlib-gen
+    mvn compile exec:java
+
+This then runs the [GenerateStandardLib.kt](https://github.com/JetBrains/kotlin/blob/master/libraries/tools/kotlin-stdlib-gen/src/generators/GenerateStandardLib.kt) script to create the source from the files for java.lang.Iterable<T> and java.util.Collection etc.