22. A system for debugging Extensible Stylesheet Language (XSL) programs, comprising: a processor configured to: automatically locate program elements including variables and selected program paths within a first code of a first XSL program; for each located program element, automatically modify the first code by an insertion into the first code of a second code for setting an XSL variable not included in the first code, the setting of the XSL variable including implementation of a routine, the routine generating a debugging comment when executed and coded in a programming language that provides an element for the maintenance of state information regarding a portion of the first code that corresponds to manipulation of the respective program element, wherein the debugging comment is based on the state information for the respective program element; and execute the modified first code; and an output device; wherein: the debugging comment is integrated with a main output of the first XSL program; for each located program element, the corresponding state information includes at least one of (a) a column and line location of the respective portion of the first code and (b) a hierarchical level of the respective program element; the processor is configured to copy code of a second XSL program to generate the first program, and adjacently display, via the output device, the code of second program and the integrated debugging comment and main output of the executed first program; the displayed code and main output are formatted such that at least a portion of the debugging comment is automatically displayed directly adjacent to at least a part of a respective portion of the displayed code to which the debugging comment corresponds; the processor is configured to, for each located variable for which the first XSL program is modified, insert into the first XSL program a copy of the variable to mimic the located variable; and the modified first XSL program including the first code is executed such that: (a) a portion of the first code that includes the program variable is executed, and (b) for the execution of the portion of the first code, a debugging comment is generated for the variable copy.
25. The system of claim 22 , wherein, for each of at least one of the located program elements, the debugging comment is indented, and an extent of the indentation corresponds to the hierarchical level of the located program element as indicated by the state information.