Adding a modern control structure to APL without changing the syntax

In the paper it is demonstrated how through the use of appropriately named defined functions and labels practically all modern control construct types can be introduced into APL, thus greatly enhancing the possibilities of writing understandable and well-structured APL programs. A technique is developed which allows the nesting of these control constructs to any arbitrary depth. A solution is presented which even allows to write coroutines in APL, hence providing a whole new scope of APL programming.