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Logic grammars and XML Schema. One of the most commonly asked questions about miniKanren is how miniKanren differs from Prolog.

Here is the answer Will Byrd gave to this question on Stack Overflow. This is a tricky question to answer, largely because there are so many variants of both miniKanren and Prolog. miniKanren and Prolog are really families of languages, which makes it difficult to compare their features, or even how they are used in practice. Because of this, please take everything I'm about to say with caution: if I say that Prolog uses depth-first search, be aware that many Prolog implementations support other search strategies, and that alternate search strategies can also be encoded at the meta-interpreter level. Using Difference Lists. I posted my enthusiasm about difference lists for Haskell earlier this month, but then became sidetracked by combinators and reading lists, so, let's get back on track.

Using Difference Lists

Difference lists are a (very) useful data structure in Prolog, particularly when it comes to parsing with definite clause grammars (DCGs) and when it comes to list construction (again, using DCGs). Why? Well, to answer that question, let's examine the structure of difference lists. » Zipper lists in Prolog Logtalking. April 30, 2013 I’m currently looking into zipper data structures.

» Zipper lists in Prolog Logtalking

Searching the web for zippering lists for prolog, the third hit is this old blog post by Daniel Lyons (hi Daniel!) : But I don’t liked the calls to reverse/2 and append/3 and their implied performance hits. So, I just rewrote the code to eliminate the calls (and start list index at 1; this is not C! Story To Tell - List Zippers in Haskell and Prolog. Earlier today I thought I’d solidify my understanding of zippers, at least with lists.

Story To Tell - List Zippers in Haskell and Prolog

I’m pretty eluded by the concept for other data structures for right now but I’m liking the idea of it for lists (though not exactly seeing the whole point of it yet). So I wrote up a quick implementation in Haskell included here: module Listzip where import List data Zipper a = Zipper [a] a [a] deriving (Show, Eq) at n l = Zipper prefix item postfix where (prefix,item,postfix) = doBreak n l [] doBreak 0 (x:xs) acc = (List.reverse acc, x, xs) doBreak n (x:xs) acc = doBreak (n-1) xs (x:acc) next (Zipper pre i (x:xs)) = Zipper (pre ++ [i]) x xs prev (Zipper pre i post) = Zipper (init pre) (last pre) (i:post) Definite Clause Grammars (DCGs) Definite Clause Grammars (DCGs) are convenient ways to represent grammatical relationships for various parsing applications.

Definite Clause Grammars (DCGs)

They can be used for natural language work, for creating formal command and programming languages. For example, DCG is an excellent tool for parsing and creating tagged input and output streams, such as HTML or XML. The index and table of contents in this documentation are generated by a Prolog program that uses DCG to parse the HTML, looking for headings and index entries. See Adventure in Prolog or Programming in Prolog by Clocksin and Mellish for tutorial information on DCGs and the difference lists used to implement them. Parsing with Difference Lists Parsing is analyzing an input stream. Difference lists are pairs of lists used to represent the list of elements (tokens, words, character codes, ...) being parsed.

In parsing applications, the first list contains the elements to be parsed. The full sentence would be represented by the full list and an empty list. ? Using Definite Clause Grammars in SWI-Prolog. Home By Anne Ogborn Thanks to Markus Triska.

Using Definite Clause Grammars in SWI-Prolog

Large sections of this tutorial are taken directly from his tutorial, which is used by permission here. Introduction1 Definite Clause Grammars2 Relating Trees To Lists3 Left Recursion4 Right-hand Context Notation5 Implicitly Passing States Around6 Parsing From Files7 Implementation8 Error Handling9 A Few Practical HintsConclusion. April 25, 2001 Introduction: SW is AI Many Semantic Web advocates have gone out of their way to disassociate their visions and projects from the Artificial Intelligence moniker.

No surprise, since the AI label has been the kiss of, if not death, at least scorn, since Lisp machines were frozen out of the marketplace during the great "AI winter" of the mid-1980s. Lisp still suffers from its association with the AI label, though it does well by being connected with the actual technologies. However, it is a curious phenomenon that the AI label tends to get dropped once the problem AI researchers were studying becomes tractable to some degree and yields practical systems. That seems to describe the Semantic Web pretty well. An aside -- one interesting phenomenon is that a lot of AI ends up, after fleeing the CS department, in Information and Library Sciences. So the Semantic Web is an AI project, and we should be proud of that fact. RDF Applications with Prolog. Published on this if you're having trouble printing code examples RDF Applications with PrologBy Bijan Parsia July 25, 2001.

RDF Applications with Prolog

SWI-Prolog. Is an atom, list of character codes, or a Prolog string. provides the arguments required by the format specification.


If only one argument is required and this single argument is not a list, the argument need not be put in a list. Otherwise the arguments are put in a list. Special sequences start with the tilde (~), followed by an optional numeric argument, optionally followed by a colon modifier (:), 116The colon modifiers is a SWI-Prolog extension, proposed by Richard O'Keefe. followed by a character describing the action to be undertaken. A numeric argument is either a sequence of digits, representing a positive decimal number, a sequence `<>, representing the character code value of the character (only useful for ~t) or a asterisk (*), in which case the numeric argument is taken from the next argument of the argument list, which should be a positive integer. E.g., the following three examples all pass 46 (.) to ~t: ? ? LtU Classic Archives. Here's an online tutorial that has some stuff on DCG's and Building Parse Trees for an expression grammar, since the basic DCG will only tell you whether the list of strings satisfies the grammar.

LtU Classic Archives

DCG's are also the natural language parsing formalism with the longest unbroken history. The tradition starts with Schieber and Pereira's classic Prolog and Natural Language Analysis that culminates in a English question answering program in DCG: "Talk". (code available at CMU AI Repository) Covington's book builds on Pereira and Schieber and adds a simple system for unification of untyped feature structures. Alan Black, Robin Cooper, Ian Lewin (1993) Prolog and Natural Language Semantics: Notes for AI3/4 Computational Semantics, also builds on Pereira and Schieber adding semantics and Discourse Representation Theory (DRT) and also has an analysis of Pereira's Chat-80 question answering program.

The most recent addition to the tradition is a set of online books on computational semantics. Prolog Programming: a do-it-yourself course for beginners. This is a course that I will teach at the 16th European Summer School in Logic, Language and Information which is going to take place in Nancy, France in August 2004.

It will be a hands-on programming course for students of linguistics who don't have any prior experience in programming. Its aim is to give linguists an impression of what it means to program and to show them how straightforward it is to do some interesting things (like writing parsers for small grammars). According to the courses's aim, its focus will be on material that leads the students to practical programming. In the first three lectures I will cover the basics of Prolog (knowledge bases and queries, matching and proof search, lists).

The last two lectures will be devoted to Definite Clause Grammars (DCGs). Programming is something which cannot be learned without actually doing it. Prolog - Count the number of leaves in a tree. Grammar - Prolog DCG illustration please. Problem - writing XML with Prolog. Permalink Raw Message Report. Prolog 3/4: XML Parsing « Virtuous Programmer. This is the third article in a series, to read it from the beginning go here. The Plan This week is when I really put the assertion that Prolog is a general purpose language to the test. Most decently rational Prolog programmers will tell you to do things like XML parsing and display through another language, then use Prolog dll's to do the interesting logical stuff. But, it does have the libraries, so let's see how they work. Coursenotes. Getting Started. This section provides a tutorial introduction to JPL through its JPL 2.x Java API overview, the interface most programmers are likely to use.

The source code described here can be found in the examples directory of the JPL distribution. Feel free to consult the source files and run the demonstration program as you read this section. Verifying the installation. Prolog Tutorial. RDF Applications with Prolog. Prolog Development Tools - ProDT - Eclipse IDE for Prolog. The Prolog Development Tool - A Prolog IDE for Eclipse [SE-Wiki] Algorithms for Computational Linguistics. Programming in XPCE/Prolog: Section 11.4. Yet More XML: with Prolog. [ Jocelyn Ireson-Paine's Home Page | Publications | Dobbs Code Talk Index | Dobbs Blog Version ] I just saw Mark Nelson's More on XML with his account of how difficult Visual C++ and MSXML make it to extract a node not all that far down from the root of an XML tree.

Help: I want the whole answer. Both the toplevel query/answer loop as the debugger abbreviate long complex terms. They do this to avoid endless pages of output. In fact, they write using write_term/3 which takes an option-list as argument. Anniepoo/amziexpertsystemsinprolog. Prolog Programming. Prolog Programming. Prolog Programming. Natural Language Processing Techniques in Prolog. Natural Language Processing With Prolog in the IBM Watson System. Prolog dcg. Case-Based Reasoning Software. Web Applications in SWI-Prolog. Prolmanual. Multilang. A Java/XML guide for prolog programmers on Windows 9X. A Java/XML guide for prolog programmers on Windows 9X.

Prolog Guide - Resources. SWI Prolog. Prolog - parse with DCG. Prolog. Welcome to the Prolog book. Section(2,'4.12',swi('/doc/Manual/DCG.html')) Using Definite Clause Grammars in SWI-Prolog. Expert Systems in Prolog. Inc. Adventure in Prolog. Csee.umbc. Simple-prolog-examples. Learn Prolog Now! InterProlog Consulting. XSB. Why did Prolog lose steam? Process CSV (Comma-Separated Values) data.