Named-readtables — Readtable Management for Common Lisp

named-readtables is a Common Lisp library that gives names to readtables, allowing them to be selected per-file with in-readtable. The standard CL readtable is a mutable global object; named-readtables provides a safe, modular alternative.

Online documentation: github.com/melisgl/named-readtables

Tolk uses named-readtables to activate the :fare-quasiquote readtable, which extends the standard quasiquote syntax to be usable as a trivia pattern. Every tolk source file that uses quasiquote patterns declares:

(named-readtables:in-readtable :fare-quasiquote)

This is a per-file declaration (like in-package). It affects only the file in which it appears. Other files retain the standard readtable unless they also declare in-readtable.

in-readtable sets *readtable* to the named readtable for the duration of loading the current file. This means any reader-macro extensions registered under that name are active when the file's forms are read.

fare-quasiquote registers itself under the name :fare-quasiquote by calling named-readtables:defreadtable.

(ql:quickload :named-readtables)

trivia.quasiquote loads named-readtables and fare-quasiquote automatically as dependencies.

• Fare-quasiquote — the readtable that named-readtables activates in tolk
• Trivia — the pattern-matching library that uses the extended readtable
• Tolk — declares in-readtable :fare-quasiquote in each parser file