sourcetosource

Sourcetosource is a term used to describe a software process or tool that translates source code from one programming language into equivalent source code in another language. Also known as a transpiler, it focuses on translating at the source level rather than compiling to machine code. The goal is to preserve program semantics, behavior, and structure as much as possible while adapting syntax, libraries, and idioms to the target language.

It is typically used to port programs to ecosystems with better tooling or performance characteristics, to modernize legacy code, or to enable developers to write in a preferred language while running in a different runtime or platform. Common use cases include translating high-level languages such as TypeScript to JavaScript, or transpiling newer JavaScript features to older runtimes using Babel, as well as cross-language ports like Python-to-JavaScript projects or academic languages to more mainstream targets.

The process generally involves parsing the source code into an abstract syntax tree, applying semantic analysis, performing transformations and optimizations, and emitting code in the target language. Source maps may accompany the output to help with debugging. Some sourcetosource tools operate as compilers with intermediate representations, while others are libraries that run within the development language’s ecosystem.

Limitations can include imperfect semantic preservation, differences in standard libraries, platform-specific semantics, and added maintenance overhead. Performance may vary depending on the quality of the translation and the target environment.