picl

PICL is a Common Lisp library that provides a comprehensive port of Python's itertools module, offering iterator utilities for sequence manipulation and combinatorial operations. It implements lazy evaluation where appropriate and avoids dependencies on cl-cont for better compatibility with Common Lisp's condition system.

Key Features

• Complete itertools port — Implements nearly all functions from Python's itertools library in Common Lisp.
• Lazy evaluation — Many iterators are lazy, producing values on demand rather than all at once.
• cl-cont independence — Designed without reliance on cl-cont, ensuring better compatibility with Common Lisp's condition system.
• Iterator protocol — Defines a simple iterator protocol using thunks that return payload and alive-indicator values.
• Iterate integration — Provides an in-it driver for seamless use with the Iterate iteration macro.
• Predefined specializations — Includes built-in make-iterator methods for lists and vectors.

Philosophy

PICL aims to bring Python's powerful itertools functionality to Common Lisp while maintaining idiomatic Lisp design and avoiding problematic dependencies.