From 0f1175588a91dca399697a1ae90d4a31cea9afc4 Mon Sep 17 00:00:00 2001 From: Kenn Knowles Date: Mon, 23 Apr 2012 11:26:43 -0700 Subject: [PATCH] Add docs --- LICENSE | 202 +++++++++++++++++++++++++++++++++++++++++++++++++++++ README.md | 85 ++++++++++++++++++++++ timing.csv | 200 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 487 insertions(+) create mode 100644 LICENSE create mode 100644 README.md create mode 100644 timing.csv diff --git a/LICENSE b/LICENSE new file mode 100644 index 0000000..d645695 --- /dev/null +++ b/LICENSE @@ -0,0 +1,202 @@ + + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. 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I have gone halfway - this is a half-baked implementation in +an esoteric language that is not really well suited to this problem. But I +did take amateurish timings that indicate the "controversial" exponential +example is certainly recognized in less than exponential time using this technique. + +Caveats: + + - This implementation is slow by a huge constant factor, for which I am + certainly to blame. Is it the emulation of algebraic data types? Are + there places I could be more mutatey? Should I put laziness in places + other than where it is needed for termination? Probably all of the above. + - Thus far, I have only implemented a recognizer, not a parser, because I + have faith that returning the head of a lazy stream of parse trees + is the same complexity. + - There are probably bugs. In particular my recursive examples do not seem + to always have the memory layout I expect, and it changes based on + unrelated code, even in other files. This seems to affect only + the pretty-printing test suite. + - I probably won't take it further because I've had my fun with Go, but I + encourage anyone interested in parsing to fork and improve, or write + their own. + +So, you can see the timings I took (on a modern-ish MacBook Pro with an SSD) in timings.csv + + +Further reading +--------------- + +In roughly reverse chronological (causal?) order. + + * [Parsing With Derivatives](http://matt.might.net/papers/might2011derivatives.pdf) by Matthew Might, David Darais, and Daniel Spiewak, International Conference on Functional Programming, 2011. + * [Yacc is dead: An update](http://matt.might.net/articles/parsing-with-derivatives/] by Matt Might on his blog. + * [Yacc Is Not Dead](http://research.swtch.com/yaccalive) by Russ Cox on his blog. + * [Yacc Is Dead](http://arxiv.org/abs/1010.5023) by Matthew Might and David Darais, rejected from ESOP 2009. + * [Regular-expression derivatives reexamined](http://www.ccs.neu.edu/home/turon/re-deriv.pdf) by Scott Owens, John Reppy, and Aaron Turon, Journal of Functional Programming, 2009. + * [Derivatives of Regular Expressions](http://dl.acm.org/citation.cfm?id=321249) by Janusz Brzozowski, Journal of the ACMi, 1964. (paywall, sorry!) + + +Copyright & License +------------------- +Copyright 2012- Kenneth Knowles + +Licensed under the Apache License, Version 2.0 (the "License"); you may not use +this file except in compliance with the License. You may obtain a copy of the +License at + +http://www.apache.org/licenses/LICENSE-2.0 + +Unless required by applicable law or agreed to in writing, software distributed +under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR +CONDITIONS OF ANY KIND, either express or implied. See the License for the +specific language governing permissions and limitations under the License. + + + diff --git a/timing.csv b/timing.csv new file mode 100644 index 0000000..56ec0a1 --- /dev/null +++ b/timing.csv @@ -0,0 +1,200 @@ +1,0.000 +2,0.000 +3,0.000 +4,0.001 +5,0.002 +6,0.002 +7,0.003 +8,0.003 +9,0.005 +10,0.005 +11,0.006 +12,0.007 +13,0.010 +14,0.012 +15,0.014 +16,0.017 +17,0.020 +18,0.023 +19,0.027 +20,0.032 +21,0.041 +22,0.046 +23,0.056 +24,0.058 +25,0.060 +26,0.067 +27,0.073 +28,0.082 +29,0.090 +30,0.101 +31,0.110 +32,0.118 +33,0.129 +34,0.141 +35,0.152 +36,0.165 +37,0.177 +38,0.192 +39,0.206 +40,0.222 +41,0.238 +42,0.254 +43,0.281 +44,0.292 +45,0.311 +46,0.333 +47,0.353 +48,0.373 +49,0.399 +50,0.421 +51,0.446 +52,0.524 +53,0.546 +54,0.549 +55,0.581 +56,0.634 +57,0.632 +58,0.647 +59,0.676 +60,0.707 +61,0.744 +62,0.785 +63,0.832 +64,0.866 +65,0.894 +66,0.957 +67,0.980 +68,1.020 +69,1.074 +70,1.137 +71,1.231 +72,1.209 +73,1.262 +74,1.310 +75,1.360 +76,1.412 +77,1.473 +78,1.503 +79,1.618 +80,1.666 +81,1.782 +82,1.755 +83,1.829 +84,1.878 +85,1.956 +86,2.029 +87,2.087 +88,2.170 +89,2.235 +90,2.285 +91,2.385 +92,2.457 +93,2.525 +94,2.608 +95,2.721 +96,2.756 +97,2.887 +98,2.975 +99,3.048 +100,3.117 +101,3.207 +102,3.327 +103,3.372 +104,3.519 +105,3.651 +106,3.708 +107,3.842 +108,3.924 +109,4.037 +110,4.152 +111,4.259 +112,4.329 +113,4.420 +114,4.553 +115,4.677 +116,4.814 +117,4.962 +118,5.069 +119,5.132 +120,5.292 +121,5.381 +122,5.528 +123,5.657 +124,5.791 +125,5.892 +126,6.030 +127,6.198 +128,6.334 +129,6.616 +130,6.622 +131,6.825 +132,7.191 +133,7.154 +134,7.376 +135,7.444 +136,7.618 +137,7.812 +138,7.943 +139,8.076 +140,8.332 +141,8.426 +142,8.589 +143,8.780 +144,9.021 +145,9.166 +146,9.351 +147,9.645 +148,9.740 +149,9.991 +150,10.122 +151,10.487 +152,10.537 +153,10.755 +154,10.974 +155,11.164 +156,11.416 +157,11.593 +158,11.839 +159,12.075 +160,12.264 +161,12.506 +162,12.754 +163,12.999 +164,13.158 +165,13.412 +166,13.715 +167,13.962 +168,14.220 +169,14.422 +170,14.851 +171,14.960 +172,15.145 +173,15.455 +174,15.718 +175,15.959 +176,16.228 +177,16.477 +178,16.739 +179,17.130 +180,17.415 +181,17.595 +182,17.879 +183,18.298 +184,18.532 +185,18.766 +186,19.072 +187,19.506 +188,19.742 +189,20.032 +190,20.269 +191,20.868 +192,20.947 +193,21.448 +194,21.566 +195,21.906 +196,22.306 +197,22.597 +198,22.901 +199,23.327 +200,23.593