inScheme

inScheme is an embeddable implementation of the Scheme programming language designed for adding scripting capabilities to applications. It emphasizes portability across platforms, a compact footprint, and a straightforward C API to facilitate integration within host software. The project aims to provide a usable subset of Scheme with core language features and a stable interface for embedding and extension.

Key features commonly cited in inScheme include first-class procedures, lexical scoping, tail recursion, and a hygienic macro system. It typically offers a read-eval-print loop (REPL) for interactive work, a module system for organizing code, and a garbage-collected runtime to manage memory automatically. The interpreter is designed to be compiled into applications as a library and linked either statically or dynamically, depending on the host project’s needs.

Architecture and API

inScheme exposes a C API that allows applications to initialize the interpreter, evaluate Scheme expressions from strings or files, and retrieve results. It also provides facilities to register host-language functions so that Scheme code can call into the surrounding application (foreign function interface, or FFI) and to expose Scheme procedures to the host program. The runtime generally supports loading and executing Scheme modules, error handling, and basic I/O operations, enabling embedding of scripting without requiring separate process boundaries.

Development and usage

Projects embed inScheme by including its headers, creating an interpreter instance, and invoking evaluation routines to run Scheme code. Applications may run a built-in REPL for debugging or load Scheme files at start-up. Ongoing development focuses on stability, portability, and expanding the available standard-library features.

History

The project is maintained as an open-source software component, with repositories typically hosted on public code platforms. It is used by developers seeking a lightweight, embeddable Scheme option for applications and prototyping.

See also

Guile, Racket, Chicken Scheme, Chez Scheme, MIT Scheme.