diff options
| author | aarne <aarne@cs.chalmers.se> | 2008-06-27 11:27:00 +0000 |
|---|---|---|
| committer | aarne <aarne@cs.chalmers.se> | 2008-06-27 11:27:00 +0000 |
| commit | e4e64c13a69db6505df499a0c3445ada9b1b2d88 (patch) | |
| tree | 28044f42fd5d30582a0478556b043f2363b6c9fb /doc/gf2-highlights.html | |
| parent | 7cdbe8e7a34e1eda300f4756c4a66ff9be027368 (diff) | |
more rm in doc
Diffstat (limited to 'doc/gf2-highlights.html')
| -rw-r--r-- | doc/gf2-highlights.html | 490 |
1 files changed, 0 insertions, 490 deletions
diff --git a/doc/gf2-highlights.html b/doc/gf2-highlights.html deleted file mode 100644 index 3d8a150a9..000000000 --- a/doc/gf2-highlights.html +++ /dev/null @@ -1,490 +0,0 @@ -<html> - -<body bgcolor="#FFFFFF" text="#000000"> - -<center> - -<h1>Grammatical Framework Version 2</h1> - -Highlights, versions 2.0, 2.1, and 2.2 (2.2 coming soon) - -<p> - -13/10/2003 - 25/11 - 2/4/2004 - 18/6 - 13/10 - 16/2/2005 - -<p> - -<a href="http://www.cs.chalmers.se/~aarne">Aarne Ranta</a> - -</center> - - -<h2>Syntax of GF</h2> - -An accurate <a href="DocGF.pdf">language specification</a> is now available. - - -<h2>Summary of novelties in Versions 2.0 to 2.2</h2> - -<h4>Module system</h4> - -<li> Separate modules for <tt>abstract</tt>, - <tt>concrete</tt>, and <tt>resource</tt>. -<li> Replaces the file-based <tt>include</tt> system -<li> Name space handling with qualified names -<li> Hierarchic structure (single inheritance <tt>**</tt>) + - cross-cutting reuse (<tt>open</tt>) -<li> Separate compilation, one module per file -<li> Reuse of <tt>abstract</tt>+<tt>concrete</tt> as <tt>resource</tt><br> - <b>Version 2.2</b>: separate <tt>reuse</tt> modules no longer needed -<li> Parametrized modules: - <tt>interface</tt>, <tt>instance</tt>, <tt>incomplete</tt>. -<li> New experimental module types: <tt>transfer</tt>, - <tt>union</tt>. -<li> Version 2.1: multiple inheritance in module extension. - -<h4>Canonical format GFC</h4> - -<li> The target of GF compiler; to reuse, just read in. -<li> Readable by Haskell/Java/C++/C applications. -<li> Version 2.1: Java interpreter available for GFC (by Björn Bringert). -<li> <b>Version 2.2</b>: new optimizations to reduce the size of GFC files - - -<h4>New features in expression language</h4> - -<li> Disjunctive patterns <tt>P | ... | Q</tt>. -<li> String patterns <tt>"foo"</tt>. -<li> Binding token <tt>&+</tt> to glue separate tokens at unlexing phase, - and unlexer to resolve this. -<li> New syntax alternatives for local definitions: <tt>let</tt> without - braces and <tt>where</tt>. -<li> Pattern variables can be used on lhs's of <tt>oper</tt> definitions. -<li> New Unicode transliterations (by Harad Hammarström). -<li> Version 2.1: Initial segments of integers - (<tt>Ints</tt><i>n</i>) available as parameter types. - - -<h4>New shell commands and command functionalities</h4> - -<li> <tt>pi</tt> = <tt>print_info</tt>: information on an identifier in scope. -<li> <tt>h</tt> = <tt>help</tt> now in long or short form, - and on individual commands. -<li> <tt>gt</tt> = <tt>generate_trees</tt>: all trees of a given - category or instantiations of a given incomplete term, up to a - given depth. -<li> <tt>gr</tt> = <tt>generate_random</tt> can now be given - an incomplete term as an argument, to constrain generation. -<li> <tt>so</tt> = <tt>show_opers</tt> shows all <tt>ope</tt> - operations with a given value type. -<li> <tt>pm</tt> = <tt>print_multi</tt> prints the multilingual - grammar resident in the current state to a ready-compiles - <tt>.gfcm</tt> file. -<li> <b>Version 2.2</b>: several new command options -<li> <b>Version 2.2</b>: <tt>vg</tt> visializes the module dependency graph -<li> All commands have both long and short names (see help). Short - names are easier to type, whereas long names - make scripts more readable. -<li> Meaningless command options generate warnings. - - -<h4>New editor features</h4> - -<li> Active text field: click the middle button in the focus to send - in refinement through the parser. -<li> Clipboard: copy complex terms into the refine menu. -<li> <b>Version 2.2</b>: text corresponding to subtrees with constraints marked with red colour - - -<h4>Improved implementation</h4> - -<li> Haskell source code is organized into subdirectories. -<li> BNF Converter is used for defining the languages GF and GFC, which also - give reliable LaTeX documentation. -<li> Lexical rules sorted out by option <tt>-cflexer</tt> for efficient - parsing with large lexica. -<li> GHC optimizations and strictness flags are used for improving performance. -<li> <b>Version 2.2</b>: started <a - href="http://www.haskell.org/haddock">haddock</a> documentation - by using uniform module headers - - - -<h4>New parser (work in progress)</h4> - -<li> By Peter Ljunglöf, based on MCFG. -<li> Much more efficient for morphology and discontinuous constituents. -<li> Treatment of cyclic rules. -<li> Version 2.1: improved generation of speech recognition - grammars (by Björn Bringert). -<li> Version 2.1: output of Labelled BNF files readable by the - BNF Converter. - - - - -<!-- NEW --> - -<h2>Abstract, concrete, and resource modules</h2> - -Judgement forms are sorted as follows: -<ul> -<li> abstract: - <tt>cat</tt>, <tt>fun</tt>, <tt>def</tt>, <tt>data</tt>, <tt>flags</tt> -<li> concrete: - <tt>lincat</tt>, <tt>cat</tt>, <tt>printname</tt>, <tt>flags</tt> -<li> resource: - <tt>param</tt>, <tt>oper</tt>, <tt>flags</tt> -<li> -</ul> -Example: -<pre> - abstract Sums = { - cat - Exp ; - fun - One : Exp ; - plus : Exp -> Exp -> Exp ; - } - - concrete EnglishSums of Sums = open ResEng in { - lincat - Exp = {s : Str ; n : Number} ; - lin - One = expSg "one" ; - sum x y = expSg ("the" ++ "sum" ++ "of" ++ x.s ++ "and" ++ y.s) ; - } - - resource ResEng = { - param - Number = Sg | Pl ; - oper - expSG : Str -> {s : Str ; n : Number} = \s -> {s = s ; n = Sg} ; - } -</pre> - - - -<!-- NEW --> - -<h2>Opening and extending modules</h2> - -A <tt>concrete</tt> or <tt>resource</tt> can <b>open</b> a -<tt>resource</tt>. This means that -<ul> -<li> the names defined in <tt>resource</tt> can be used ("become visible") -<li> but: these names are not included in ("exported from") the opening module -</ul> -A module of any type can moreover <b>extend</b> a module of the same type. -This means that -<ul> -<li> the names defined in the extended module can be used ("become visible") -<li> and also: these names are included in ("exported from") the extending module -</ul> -Examples of extension: -<pre> - abstract Products = Sums ** { - fun times : Exp -> Exp -> Exp ; - } - -- names exported: Exp, plus, times - - concrete English of Products = EnglishSums ** open ResEng in { - lin times x y = expSg ("the" ++ "product" ++ "of" ++ x.s ++ "and" ++ y.s) ; - } -</pre> - -<p> - -Opening, but not extension, can be <b>qualified</b>: -<pre> - concrete NumberSystems of Systems = open (Bin = Binary), (Dec = Decimal) in { - lin - BZero = Bin.Zero ; - DZero = Dec.Zero - } -</pre> - -<p> - -<b>Version 2.1</b> introduces <tt>multiple inheritance</tt>: a module -can extend several modules at the same time, for instance, -<pre> - abstract Dialogue = User, System ** { ...} -</pre> -may be used to put together "User's moves" and "System's moves" into -one Dialogue System grammar. - - - -<!-- NEW --> - -<h2>Compiling modules</h2> - -Separate compilation assumes there is <b>one module per file</b>. - -<p> - -The <b>module header</b> is the beginning of the module code up to the -first left bracket (<tt>{</tt>). The header gives -<ul> -<li> the module type: <tt>abstract</tt>, <tt>concrete</tt> (<tt>of</tt> <i>A</i>), - or <tt>resource</tt> -<li> the name of the module (next to the module type keyword) -<li> the names of extended modules (between <tt>=</tt> and <tt>**</tt>) -<li> the names of opened modules -</ul> - -<p> - -<b>filename</b> = <b>modulename</b> <tt>.</tt> <b>extension</b> - -<p> - -File name extensions: -<ul> -<li> <tt>gf</tt>: GF source file (uses GF syntax, is type checked and compiled) -<li> <tt>gfc</tt>: canonical GF file (uses GFC syntax, is simply read -in instead of compiled; produced from all kinds of modules) -<li> <tt>gfr</tt>: GF resource file (uses GF syntax, is only read in; produced from -<tt>resource</tt> modules) -<li> <tt>gfcm</tt>: canonical multilingual GF file -(uses GFC syntax, is only read in; produced -from a set of <tt>abstract</tt> and <tt>conctrete</tt> modules) -</ul> -Only <tt>gf</tt> files should ever be written/edited manually! - -<p> - -What the make facility does when compiling <tt>Foo.gf</tt> -<ol> -<li> read the module header of <tt>Foo.gf</tt>, and recursively all headers from -the modules it <b>depends</b> on (i.e. extends or opens) -<li> build a dependency graph of these modules, and do topological sorting -<li> starting from the first module in topological order, -compare the modification times of each <tt>gf</tt> and <tt>gfc</tt> file: -<ul> -<li> if <tt>gf</tt> is later, compile the module and all modules depending on it -<li> if <tt>gfc</tt> is later, just read in the module -</ul> -</ol> -Inside the GF shell, also time stamps of modules read into memory are -taken into account. Thus a module need not be read from a file if the -module is in the memory and the file has not been modified. - -<p> - -If the compilation of a grammar fails at some module, the state of the -GF shell contains all modules read up to that point. This makes it -faster to compile the faulty module again after fixing it. - -<p> - -Use the command <tt>po</tt> = <tt>print_options</tt> to see what -modules are in the state. - -<p> - -To force compilation: -<ul> -<li> The flag <i>-src</i> in the import command forces compilation from - source even if more recent object files exist. This is useful - when testing new versions of GF. -<li> The flag <i>-retain</i> in the import command forces reading in - <tt>gfr</tt> files in addition to <tt>gfc</tt> files. This is useful - when testing operations with the <tt>cc</tt> command. -</ul> - -<!-- NEW --> - -<h3>Compiler optimizations</h3> - -<b>Version 2.2</b> - -<p> - -The sometimes exploding size of generated <tt>gfc</tt> and -<tt>gfr</tt> files has made it urgent to find optimizations -that reduce the size of the code. There are five -combinations optimizations that can be chosen, as the value of the -<tt>optimize</tt> flag: -<ul> -<li> <tt>share</tt>: group tables so that common branch values are shared -by the use of disjunctive patterns. -<li> <tt>parametrize</tt>: if table branches differ at most at the -occurrence of the pattern, replace the expanded table by a one-branch -table with a variable. If this fails, perform <tt>share</tt>. -<li> <tt>values</tt>: only show the values of table branches, not the -patterns. -<li> <tt>all</tt>: try <tt>parametrize</tt>; if this fails, do <tt>values</tt>. -<li> <tt>none</tt>: don't do any optimizations -</ul> -The <tt>share</tt> and <tt>parametrize</tt> optimizations are always -just good, whereas the <tt>values</tt> optimization may slow down the -use of the table. However, it is very good for grammars mostly consisting -of the inflection tables of lexical items: it can reduce the file size -by the factor of 4. - -<p> - -An optimization can be selected individually for each -<tt>resource</tt> and <tt>concrete</tt> module by including -the judgement -<pre> - flags optimize=(share|parametrize|values|all|none) ; -</pre> -in the module body. These flags can be overridden by a flag given -in the <tt>i</tt> command, e.g. -<pre> - i -src -optimize=none Foo.gf -</pre> -Notice that the option <tt>-src</tt> is needed if there already are -generated files created with other optimization flags. - - - -<!-- NEW --> - -<h2>Module search paths</h2> - -Modules can reside in different directories. Use the <tt>path</tt> -flag to extend the directory search path. For instance, -<pre> - -path=.:../resource/russian:../prelude -</pre> -enables files to be found in three different directories. -By default, only the current directory is included. -If a <tt>path</tt> flag is given, the current directory -<tt>.</tt> must be explicitly included if it is wanted. - -<p> - -The <tt>path</tt> flag can be set in any of the following -places: -<ul> -<li> when invoking GF: <tt>gf -path=xxx</tt> -<li> when importing a module: <tt>i -path=xxx Foo.gf</tt> -<li> as a pragma in a topmost file: <tt>--# -path=xxx</tt> -</ul> -A flag set on a command line overrides ones set in files. - - -<!-- NEW --> - -<h2>How to use GF 1.* files</h2> - -Backward compatibility with respect to old GF grammars has been -a central goal. All GF grammars, from version 0.9, should work in -the old way in GF2. The main exceptions are some features that -are rarely used. -<ul> -<li> The <tt>package</tt> system introduced in GF 1.2, cannot be - interpreted in the module system of GF 2.0, since packages are in - mutual scope with the top level. -<li> <tt>tokenizer</tt> pragmas are cannot be parsed any more. In GF - 1.2, they are already replaced by <tt>lexer</tt> flags. -<li> <tt>var</tt> pragmas cannot be parsed any more. -</ul> - -<p> - -Very old GF grammars (from versions before 0.9), with the completely -different notation, do not work. They should be first converted to -GF1 by using GF version 1.2. - -<p> - -The import command <tt>i</tt> can be given the option <tt>-old</tt>. E.g. -<pre> - i -old tut1.Eng.g2 -</pre> -But this is no more necessary: GF2 detects automatically if a grammar -is in the GF1 format. - -<p> - -Importing a set of GF2 files generates, internally, three modules: -<pre> - abstract tut1 = ... - resource ResEng = ... - concrete Eng of tut1 = open ResEng in ... -</pre> -(The names are different if the file name has fewer parts.) - - -<p> - -The option <tt>-o</tt> causes GF2 to write these modules into files. - -<p> - -The flags <tt>-abs</tt>, <tt>-cnc</tt>, and <tt>-res</tt> can be used -to give custom names to the modules. In particular, it is good to use -the <tt>-abs</tt> flag to guarantee that the abstract syntax module -has the same name for all grammars in a multilingual environmens: -<pre> - i -old -abs=Numerals hungarian.gf - i -old -abs=Numerals tamil.gf - i -old -abs=Numerals sanskrit.gf -</pre> - -<p> - -The same flags as in the import command can be used when invoking -GF2 from the system shell. Many grammars can be imported on the same command -line, e.g. -<pre> - % gf2 -old -abs=Tutorial tut1.Eng.gf tut1.Fin.gf tut1.Fra.gf -</pre> - -<p> - -To write a GF2 grammar back to GF1 (as one big file), use the command -<pre> - > pg -old -</pre> - - -<p> - - -GF2 has more reserved words than GF 1.2. When old files are read, a preprocessor -replaces every identifier that has the shape of a new reserved word -with a variant where the last letter is replaced by <tt>Z</tt>, e.g. -<tt>instance</tt> is replaced by <tt>instancZ</tt>. This method is of course -unsafe and should be replaced by something better. - - -<!-- NEW --> - -<h2>Missing features of GF 1.2 (13/10/2004)</h2> - -Generally, GF1 grammars can be automatically translated to GF2, although the -result is not as good -as manual, since indentation and comments are destroyed. -The results can be -saved in GF2 files, but this is not necessary. -Some rarely used GF1 features are no longer supported (see next section). -It is also possible to write a GF2 grammar back to GF1, with the -command <tt>pg -printer=old</tt>. - - -<p> - -Resource libraries -and some example grammars have been -converted. Most old example grammars work without any changes. -However, there is a new resource API with -many new constructions, and which is recommended. - -<p> - -Soundness checking of module depencencies and completeness is not -complete. This means that some errors may show up too late. - -<p> - -Latex and XML printing of grammars do not work yet. - - -</body> -</html> |