Replacements and Replaceables: Making the Case for Code Variants

There are often multiple ways to implement the same requirement in source code. Different implementation choices can result in code snippets that are similar, and have been defined in multiple ways: code clones, examples, simions and variants. Currently, there is a lack of a consistent and unambiguous definition of such types of code snippets. Here we present a characterization study of code variants - a specific type of code snippets that differ from each other by at least one desired property, within a given code context. We distinguish code variants from other types of redundancies in source code, and demonstrate the significant role that they play: about 25% to 43% of developer discussions (in a set of nine open source projects) were about variants. We characterize different types of variants based on their code context and desired properties. As a demonstration of the possible use of our characterization of code variants, we show how search results can be ranked based on a desired property (e.g., speed of execution).