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diff --git a/doc/gf-tutorial.html b/doc/gf-tutorial.html index fcf5683d4..18e353a23 100644 --- a/doc/gf-tutorial.html +++ b/doc/gf-tutorial.html @@ -238,19 +238,23 @@ Version 3.1.2, November 2008 <LI><A HREF="#toc149">Producing GFCC for the translator</A> <LI><A HREF="#toc150">A translator loop</A> <LI><A HREF="#toc151">A question-answer system</A> - <LI><A HREF="#toc152">Exporting GF datatypes to Haskell</A> - <LI><A HREF="#toc153">Example of exporting GF datatypes</A> + <LI><A HREF="#toc152">Abstract syntax of the query system</A> + <LI><A HREF="#toc153">Exporting GF datatypes to Haskell</A> <LI><A HREF="#toc154">The question-answer function</A> <LI><A HREF="#toc155">Converting between Haskell and GF trees</A> <LI><A HREF="#toc156">Putting it all together: the transfer definition</A> <LI><A HREF="#toc157">Putting it all together: the Main module</A> <LI><A HREF="#toc158">Putting it all together: the Makefile</A> - <LI><A HREF="#toc159">Translets: embedded translators in Java</A> - <LI><A HREF="#toc160">Dialogue systems in Java</A> </UL> - <LI><A HREF="#toc161">Language models for speech recognition</A> + <LI><A HREF="#toc159">Web server applications</A> + <LI><A HREF="#toc160">JavaScript applications</A> <UL> - <LI><A HREF="#toc162">More speech recognition grammar formats</A> + <LI><A HREF="#toc161">Compiling to JavaScript</A> + <LI><A HREF="#toc162">Using the JavaScript grammar</A> + </UL> + <LI><A HREF="#toc163">Language models for speech recognition</A> + <UL> + <LI><A HREF="#toc164">More speech recognition grammar formats</A> </UL> </UL> </UL> @@ -5232,10 +5236,10 @@ point literals as arguments. Goals: </P> <UL> -<LI>use as parts of programs written in other programming Haskell and Java +<LI>use grammars as parts of programs written in Haskell and JavaScript <LI>implement stand-alone question-answering systems and translators based on GF grammars -<LI>generate language models for speech recognition from grammars +<LI>generate language models for speech recognition from GF grammars </UL> <P> @@ -5245,13 +5249,13 @@ Goals: <H2>Functionalities of an embedded grammar format</H2> <P> GF grammars can be used as parts of programs written in other programming -languages. Haskell and Java. +languages, to be called <B>host languages</B>. This facility is based on several components: </P> <UL> -<LI>a portable format for multilingual GF grammars -<LI>an interpreter for this format written in the host language -<LI>an API that enables reading grammar files and calling the interpreter +<LI>PGF: a portable format for multilingual GF grammars +<LI>a PGF interpreter written in the host language +<LI>a library in the host language that enables calling the interpreter <LI>a way to manipulate abstract syntax trees in the host language </UL> @@ -5264,23 +5268,13 @@ This facility is based on several components: The portable format is called PGF, "Portable Grammar Format". </P> <P> -A file can be produced in GF by the command -</P> -<PRE> - > print_grammar | write_file FILE.pgf -</PRE> -<P> -There is also a batch compiler, executable from the operative system shell: +This format is produced by the GF batch compiler <CODE>gfc</CODE>, +executable from the operative system shell: </P> <PRE> % gfc --make SOURCE.gf </PRE> <P> -<I>This applies to GF version 3 and upwards. Older GF used a format suffixed</I> -<CODE>.gfcm</CODE>. -<I>At the moment of writing, also the Java interpreter still uses the GFCM format.</I> -</P> -<P> PGF is the recommended format in which final grammar products are distributed, because they are stripped from superfluous information and can be started and applied @@ -5456,50 +5450,60 @@ To reply in the <I>same</I> language as the question: <!-- NEW --> </P> <A NAME="toc152"></A> +<H3>Abstract syntax of the query system</H3> +<P> +Input: abstract syntax judgements +</P> +<PRE> + abstract Query = { + + flags startcat=Question ; + + cat + Answer ; Question ; Object ; + + fun + Even : Object -> Question ; + Odd : Object -> Question ; + Prime : Object -> Question ; + Number : Int -> Object ; + + Yes : Answer ; + No : Answer ; + } +</PRE> +<P></P> +<P> +<!-- NEW --> +</P> +<A NAME="toc153"></A> <H3>Exporting GF datatypes to Haskell</H3> <P> To make it easy to define a transfer function, we export the abstract syntax to a system of Haskell datatypes: </P> <PRE> - % gfc --output-format=haskell Food.gfcc + % gfc --output-format=haskell Query.pgf </PRE> <P> It is also possible to produce the Haskell file together with GFCC, by </P> <PRE> - % gfc --make --output-format=haskell FoodEng.gf FoodIta.gf + % gfc --make --output-format=haskell QueryEng.gf </PRE> <P> -The result is a file named <CODE>Food.hs</CODE>, containing a -module named <CODE>Food</CODE>. +The result is a file named <CODE>Query.hs</CODE>, containing a +module named <CODE>Query</CODE>. </P> <P> <!-- NEW --> </P> -<A NAME="toc153"></A> -<H3>Example of exporting GF datatypes</H3> -<P> -Input: abstract syntax judgements -</P> -<PRE> - cat - Answer ; Question ; Object ; - - fun - Even : Object -> Question ; - Odd : Object -> Question ; - Prime : Object -> Question ; - Number : Int -> Object ; - - Yes : Answer ; - No : Answer ; -</PRE> <P> Output: Haskell definitions </P> <PRE> - newtype GInt = GInt Integer + module Query where + import PGF data GAnswer = GYes @@ -5511,6 +5515,8 @@ Output: Haskell definitions GPrime GObject | GOdd GObject | GEven GObject + + newtype GInt = GInt Integer </PRE> <P> All type and constructor names are prefixed with a <CODE>G</CODE> to prevent clashes. @@ -5571,8 +5577,8 @@ For the programmer, it is enougo to know: </P> <UL> <LI>all GF names are in Haskell prefixed with <CODE>G</CODE> -<LI><CODE>gf</CODE> translates from Haskell to GF -<LI><CODE>fg</CODE> translates from GF to Haskell +<LI><CODE>gf</CODE> translates from Haskell objects to GF trees +<LI><CODE>fg</CODE> translates from GF trees to Haskell objects </UL> <P> @@ -5584,7 +5590,7 @@ For the programmer, it is enougo to know: module TransferDef where import PGF (Tree) - import Math -- generated from GF + import Query -- generated from GF transfer :: Tree -> Tree transfer = gf . answer . fg @@ -5625,7 +5631,7 @@ Here is the complete code in the Haskell file <CODE>TransferLoop.hs</CODE>. main :: IO () main = do - gr <- file2grammar "Math.pgf" + gr <- readPGF "Query.pgf" loop (translate transfer gr) loop :: (String -> String) -> IO () @@ -5636,7 +5642,7 @@ Here is the complete code in the Haskell file <CODE>TransferLoop.hs</CODE>. loop trans translate :: (Tree -> Tree) -> PGF -> String -> String - translate tr gr = case parseAllLang gr (startCat gr) s of + translate tr gr s = case parseAllLang gr (startCat gr) s of (lg,t:_):_ -> linearize gr lg (tr t) _ -> "NO PARSE" </PRE> @@ -5651,7 +5657,7 @@ To automate the production of the system, we write a <CODE>Makefile</CODE> as fo </P> <PRE> all: - gfc --make -haskell MathEng.gf MathFre.gf + gfc --make --output-format=haskell QueryEng ghc --make -o ./math TransferLoop.hs strip math </PRE> @@ -5683,91 +5689,81 @@ Just to summarize, the source of the application consists of the following files <!-- NEW --> </P> <A NAME="toc159"></A> -<H3>Translets: embedded translators in Java</H3> +<H2>Web server applications</H2> <P> -<B>NOTICE</B>. Only for GF 2.9 and older at the moment. +PGF files can be used in web servers, for which there is a Haskell library included +in <CODE>src/server/</CODE>. How to build a server for tasks like translators is explained +in the <A HREF="../src/server/README"><CODE>README</CODE></A> file in that directory. </P> <P> -A Java system needs many more files than a Haskell system. -To get started, fetch the package <CODE>gfc2java</CODE> from +One of the servers that can be readily built with the library (without any +programming required) is <B>fridge poetry magnets</B>. It is an application that +uses an incremental parser to suggest grammatically correct next words. Here +is an example of its application to the <CODE>Foods</CODE> grammars. </P> <P> -<A HREF="http://www.cs.chalmers.se/~bringert/darcs/gfc2java/"><CODE>www.cs.chalmers.se/~bringert/darcs/gfc2java/</CODE></A> +<IMG ALIGN="middle" SRC="food-magnet.png" BORDER="0" ALT=""> </P> <P> -by using the Darcs version control system as described in this page. +<!-- NEW --> </P> +<A NAME="toc160"></A> +<H2>JavaScript applications</H2> <P> -The <CODE>gfc2java</CODE> package contains a script <CODE>build-translet</CODE>, which -can be applied -to any <CODE>.gfcm</CODE> file to create a <B>translet</B>, a small translation GUI. +JavaScript is a programming language that has interpreters built in in most +web browsers. It is therefore usable for client side web programs, which can even +be run without access to the internet. The following figure shows a JavaScript +program compiled from GF grammars as run on an iPhone. </P> <P> -For the <CODE>Food</CODE> -grammars of <a href="#chapthree">Lesson 2</a>, we first create a file <CODE>food.gfcm</CODE> by +<IMG ALIGN="middle" SRC="iphone.jpg" BORDER="0" ALT=""> </P> -<PRE> - % echo "pm | wf food.gfcm" | gf FoodEng.gf FoodIta.gf -</PRE> <P> -and then run +<!-- NEW --> </P> -<PRE> - % build_translet food.gfcm -</PRE> +<A NAME="toc161"></A> +<H3>Compiling to JavaScript</H3> <P> -The resulting file <CODE>translate-food.jar</CODE> can be run with +JavaScript is one of the output formats of the GF batch compiler. Thus the following +command generates a JavaScript file from two <CODE>Food</CODE> grammars. </P> <PRE> - % java -jar translate-food.jar + % gfc --make --output-format=js FoodEng.gf FoodIta.gf </PRE> <P> -The translet looks like this: -</P> -<P> -<IMG ALIGN="middle" SRC="food-translet.png" BORDER="0" ALT=""> +The name of the generated file is <CODE>Food.js</CODE>, derived from the top-most abstract +syntax name. This file contains the multilingual grammar as a JavaScript object. </P> <P> <!-- NEW --> </P> -<A NAME="toc160"></A> -<H3>Dialogue systems in Java</H3> -<P> -<B>NOTICE</B>. Only for GF 2.9 and older at the moment. -</P> -<P> -A question-answer system is a special case of a <B>dialogue system</B>, -where the user and -the computer communicate by writing or, even more properly, by speech. -The <CODE>gf-java</CODE> -homepage provides an example of a most simple dialogue system imaginable, -where two -the conversation has just two rules: -</P> -<UL> -<LI>if the user says <I>here you go</I>, the system says <I>thanks</I> -<LI>if the user says <I>thanks</I>, the system says <I>you are welcome</I> -</UL> - +<A NAME="toc162"></A> +<H3>Using the JavaScript grammar</H3> <P> -The conversation can be made in both English and Swedish; the user's initiative -decides which language the system replies in. Thus the structure is very similar -to the <CODE>math</CODE> program <a href="#secmathprogram">here</a>. +To perform parsing and linearization, the run-time library +<CODE>gflib.js</CODE> is used. It is included in <CODE>GF/lib/javascript/</CODE>, together with +some other JavaScript and HTML files; these files can be used +as templates for building applications. </P> <P> -The GF and Java sources of the program can be -found in +An example of usage is +<A HREF="../lib/javascript/translator.html"><CODE>translator.html</CODE></A>, +which is in fact initialized with +a pointer to the Food grammar, so that it provides translation between the English +and Italian grammars: </P> <P> -[<CODE>www.cs.chalmers.se/~bringert/darcs/simpledemo http://www.cs.chalmers.se/~bringert/darcs/simpledemo</CODE>] +<IMG ALIGN="middle" SRC="food-js.png" BORDER="0" ALT=""> </P> <P> -again accessible with the Darcs version control system. +The grammar must have the name <CODE>grammar.js</CODE>. The abstract syntax and start +category names in <CODE>translator.html</CODE> must match the ones in the grammar. +With these changes, the translator works for any multilingual GF grammar. </P> <P> <!-- NEW --> </P> -<A NAME="toc161"></A> +<A NAME="toc163"></A> <H2>Language models for speech recognition</H2> <P> The standard way of using GF in speech recognition is by building @@ -5814,7 +5810,7 @@ Example: GSL generated from <CODE>FoodsEng.gf</CODE>. <P> <!-- NEW --> </P> -<A NAME="toc162"></A> +<A NAME="toc164"></A> <H3>More speech recognition grammar formats</H3> <P> Other formats available via the <CODE>--output-format</CODE> flag include: |