positional-lambda is a concise, intuitive and flexible syntax (macro) for trivial lambdas that eschews explicit (and often contextually-redundant) naming of parameter variables in favor of positional references, with support for a used or ignored &rest parameter and automatic declaration of ignored parameters when logical "gaps" are left in the positional references. Further convenience features are provided.

positional-lambda is in Quicklisp:

(ql:quickload "positional-lambda")

See the project's home for further information. Actual documentation is in the README.
This library is in the Public Domain. See the UNLICENSE file for details.

convenience library