Extracting reusable functions by program slicing
Filippo Lanubile, Giuseppe Visaggio · 1996
1 An alternative approach to developing reusable components from scratch is to recover them from existing systems. In this paper, we apply program slicing, introduced by Weiser, to the problem of extracting reusable functions from ill-structured programs. We extend the definition of program slice to a transform slice, one that includes statements which contribute directly or indirectly to transform a set of input variables into a set of output variables. Unlike conventional program slicing, these statements do not include neither the statements necessary to get input data nor the statements which test the binding conditions of the function. Transform slicing presupposes the knowledge that a function is performed in the code and its partial specification, only in terms of input and output data. Using domain knowledge we discuss how to formulate expectations of the functions implemented in the code. In addition to the input/output parameters of the function, the slicing criterion depend...