ISLISP (also capitalized as ISLisp) is a programming language in the Lisp family standardized by the International Organization for Standardization (ISO) and International Electrotechnical Commission (IEC) joint working group ISO/IEC JTC 1/SC 22/WG 16 (commonly termed simply SC22/WG16 or WG16). The primary output of this working group was an international standard, published by ISO. The standard was updated in 2007 and republished as ISO/IEC 13816:2007(E). Although official publication was through ISO, versions of the ISLISP language specification are available that are believed to be in the public domain. The goal of this standards effort was to define a small, core language to help bridge the gap between differing dialects of Lisp. It attempted to accomplish this goal by studying primarily Common Lisp, EuLisp, Le Lisp, and Scheme and standardizing only those features shared between them.

Design goals

ISLISP has these design goals: ISLISP has separate function and variable namespaces (hence it is a Lisp-2). ISLISP's object system, ILOS, is mostly a subset of the Common Lisp Object System (CLOS).

Major differences from Common Lisp

Implementations

ISLISP implementations have been made for many operating systems including: Windows, most Unix and POSIX based (Linux, macOS, FreeBSD, OpenBSD, NetBSD, Solaris, HP-UX, AIX, Cygwin, QNX), Android, DOS, OS/2, Pocket PC, OpenVMS, and z/OS. Implementations for hardware computer architectures include: x86, x86-64, IA-64, SPARC, SPARC9, PowerPC, MIPS, Alpha, PA-RISC, ARM, AArch64 Two older implementations are no longer available: