Trivia

[[https://travis-ci.org/guicho271828/trivia][https://travis-ci.org/guicho271828/trivia.svg?branch=master]]

• news! new pattern: lambda-list pattern. Contributed by akssri
• news! new pattern: number-related patterns, e.g. >, <, =, <= ...
• news! Inline pattern implemented ! : @, @@ ...
• news!(04/02/2016) Support for fare-quasiquote is now available. See =test/quasiquote= for the usage
• news!(04/22/2016) Added metabang-bind like macros =if-match=, =when-match=, =unless-match=, =let-match=, =let*-match=, =let-match1=
• news!(05/21/2016) Added support for minor implementations: CMU, ECL, CLISP, ABCL.
• news!(05/22/2016) Implemented =ARRAY=, =SIMPLE-ARRAY=, =ARRAY-ROW-MAJOR=, =ARRAY-ROW-MAJOR*= patterns! Multi-dimentional arrays are now more handy!
• news!(07/21/2016) Added =READ=, =LAST=, =SPLIT=, =SPLIT*= patterns! Parsing the string is more conveninent.
• news!(01/21/2017) Added =DYNAMIC= pattern! Careful use of this pattern can impact the performance sensitive code.
• news!(04/08/2017) Added a new contrib package =TRIVIA.CFFI= which provides =->= pattern ! Offers convenient access to foreign objects.
• news!(05/26/2018) Added =property!=, which only matches when the key is present in a plist.
• news!(09/06/2018) SPLIT symbol was exported from the =trivia.ppcre= package.
• news!(02/19/2019) Added =MEMBER= pattern. When the argument is a constant, it also adds type declaration.
• news!(04/24/2019) Improved the compilation of =GUARD= pattern. It no longer uses the internal hackery.
• news!(04/24/2019) Balland2006 optimizer is now the default optimizer for the pattern compiler!
• news!(04/28/2019) Added a =progv= pattern, which can dynamically alter the dynamic variable the value will be bound to.
• news!(05/08/2019) Now the optimizer can be specified in the lexical environment via =(declare (trivia:optimizer <name>))= (e.g. =(declare (trivia:optimizer :trivial))=). Implemented through cltl2 API.
• news!(10/11/2019) The OR1 consistency checking algorithm in Level 1 no longer takes the exponential runtime. Compilation of [[https://github.com/guicho271828/type-r][type-r]] library is now 10x faster! (patch from @pfdietz)
• news!(01/01/2021) Added =HASH-TABLE-ENTRY=, =HASH-TABLE-ENTRIES= patterns, and corresponding =!= suffixed patterns for matching only if key is present in hash table.
• news!(05/30/2021 Added support for [[https://github.com/slburson/fset][FSet]]. See [[test/fset.lisp][tests]] for how-to.

• Trivia : Trivial Pattern Matching Compiler

Trivia is a pattern matching compiler that is compatible with Optima. It shares the same testing code with Optima and acts as a drop-in replacement for 99% usage. For the basic usage, consult [[https://github.com/guicho271828/trivia/wiki][our wiki]]. Known differences between Optima and Trivia, which are bug, are [[https://github.com/guicho271828/trivia/wiki/Known-Differences][described here]] (7/31/2016)

#+BEGIN_SRC diff (defpackage :playwithit (:use :cl

•   :optima))
  

•   :trivia))
  

(in-package :playwithit)

(match '(something #(0 1 2)) ((list a (vector 0 _ b)) (values a b))) ;; --> SOMETHING, 2 #+END_SRC

Patterns compiled with Trivia runs [[https://github.com/guicho271828/trivia/wiki/Benchmarking-Results][faster than Optima]].

| runtime [sec] | [[https://github.com/guicho271828/trivia/blob/master/bench/definitions.lisp#L11][fibonacci]] | [[https://github.com/guicho271828/trivia/blob/master/bench/definitions.lisp#L40][gomoku]] | [[https://github.com/guicho271828/trivia/blob/master/bench/definitions.lisp#L214][string-match]] | |---------------+-----------+--------+--------------| | optima | 11.5 | 39.8 | 82.5 | | trivia [1] | 9.68 | 37.4 | 1.57 |

[1]: trivia is using :balland2006 optimiizer

... and Trivia is more extensible. In fact, Trivia's =defpattern= is able to implement all of [[https://github.com/m2ym/optima#constructor-pattern][unmodifiable, core pattern language]] in Optima within itself.

#+BEGIN_SRC lisp (defpattern cons (a b) (with-gensyms (it) `(guard1 (,it :type cons) (consp ,it) (car ,it) ,a (cdr ,it) ,b))) #+END_SRC

Detailed documentation is in [[https://github.com/guicho271828/trivia/wiki][github wiki]].

• Dependency & Testing

• Level 0,1 : Alexandria only.
• Level 2 : Additionally, lisp-namespace and closer-mop.

To run the tests, =(asdf:test-system :trivia)= .

To run the benchmark, =(asdf:test-system :trivia.benchmark)=