1. A method comprising: generating a plurality of Intermediate Language (IL) islands, each of the plurality of IL islands being callable by an interpreter to enable a debugger to debug source code; including in at least one of the plurality of IL islands a call to a function; mapping each of the plurality of IL islands to a respective text span in the source code; interpreting the source code by the interpreter by parsing the source code for commands; and calling a respective one of the plurality of IL islands istan4 with the interpreter when processing the text span in the source code corresponding to the respective one of the plurality of IL islands, said calling signaling to the debugger that the interpreter is to execute the corresponding text span; said calling a respective one of the plurality of IL islands comprising passing a function pointer to the debugger.