A mechanism is disclosed for building and using an index for searching computer programs. The method involves building an index based on two or more computer programs that have a different set of semantics for defining symbols. More particularly, a determination is made as to whether a first symbol in a first program is being defined in the first program. The determination is based upon an understanding of a first set of semantics that the first program has for defining symbols. In response to a determination that the first symbol is being defined in the first program, the first symbol is added to a definition index, along with an indicator of the first program, to indicate that the first symbol is defined in the first program.