diff options
| author | aarne <aarne@cs.chalmers.se> | 2006-04-04 07:41:32 +0000 |
|---|---|---|
| committer | aarne <aarne@cs.chalmers.se> | 2006-04-04 07:41:32 +0000 |
| commit | f1000ca8c3c07f851f1f278fc75fdf7caec9848e (patch) | |
| tree | 9d6aac83705f2ad177185afc8f22d933f1cc7e34 /doc/gf-reference.html | |
| parent | 07c7333c0fe7a566f920fb31898b0109757cc20e (diff) | |
version 3 of quick reference
Diffstat (limited to 'doc/gf-reference.html')
| -rw-r--r-- | doc/gf-reference.html | 97 |
1 files changed, 50 insertions, 47 deletions
diff --git a/doc/gf-reference.html b/doc/gf-reference.html index f019a383d..c5c108760 100644 --- a/doc/gf-reference.html +++ b/doc/gf-reference.html @@ -7,45 +7,48 @@ <P ALIGN="center"><CENTER><H1>GF Quick Reference</H1> <FONT SIZE="4"> <I>Aarne Ranta</I><BR> -Wed Mar 29 13:21:48 2006 +Tue Apr 4 09:41:30 2006 </FONT></CENTER> <P></P> <HR NOSHADE SIZE=1> <P></P> - <UL> - <LI><A HREF="#toc1">A Quick Example</A> - <LI><A HREF="#toc2">Modules and files</A> - <LI><A HREF="#toc3">Judgements</A> - <LI><A HREF="#toc4">Types</A> - <LI><A HREF="#toc5">Expressions</A> - <LI><A HREF="#toc6">Pattern matching</A> - <LI><A HREF="#toc7">Sample library functions</A> - <LI><A HREF="#toc8">Flags</A> - <LI><A HREF="#toc9">File paths</A> - <LI><A HREF="#toc10">Alternative grammar formats</A> - <LI><A HREF="#toc11">References</A> - </UL> + <UL> + <LI><A HREF="#toc1">A complete example</A> + <LI><A HREF="#toc2">Modules and files</A> + <LI><A HREF="#toc3">Judgements</A> + <LI><A HREF="#toc4">Types</A> + <LI><A HREF="#toc5">Expressions</A> + <LI><A HREF="#toc6">Pattern matching</A> + <LI><A HREF="#toc7">Sample library functions</A> + <LI><A HREF="#toc8">Flags</A> + <LI><A HREF="#toc9">File paths</A> + <LI><A HREF="#toc10">Alternative grammar formats</A> + <LI><A HREF="#toc11">References</A> + </UL> <P></P> <HR NOSHADE SIZE=1> <P></P> <P> -This is a quick reference on GF grammars. +This is a quick reference on GF grammars. It aims to +cover all forms of expression available when writing +grammars. It assumes basic knowledge of GF, which +can be acquired from the +<A HREF="http://www.cs.chalmers.se/~aarne/GF/doc/tutorial/">GF Tutorial</A>. Help on GF commands is obtained on line by the -help command (<CODE>h</CODE>). +help command (<CODE>help</CODE>), and help on invoking +GF with (<CODE>gf -help</CODE>). </P> <A NAME="toc1"></A> -<H2>A Quick Example</H2> +<H3>A complete example</H3> <P> -This is a complete example, dividing a grammar -into three files. +This is a complete example of a GF grammar divided +into three modules in files. The grammar recognizes the +phrases <I>one pizza</I> and <I>two pizzas</I>. </P> <P> -<CODE>abstract</CODE>, <CODE>concrete</CODE>, and <CODE>resource</CODE>. -</P> -<P> -File <CODE>Order.gf</CODE> +File <CODE>Order.gf</CODE>: </P> <PRE> abstract Order = { @@ -83,7 +86,7 @@ File <CODE>Res.gf</CODE>: oper regNoun : Str -> {s : Num => Str} = \dog -> {s = table { Sg => dog ; - Pl => dog + "s" + _ => dog + "s" } } ; } @@ -99,7 +102,7 @@ To use this example, do </PRE> <P></P> <A NAME="toc2"></A> -<H2>Modules and files</H2> +<H3>Modules and files</H3> <P> One module per file. File named <CODE>Foo.gf</CODE> contains module named @@ -163,7 +166,7 @@ Comments have the forms <PRE> -- till the end of line {- any number of lines between -} - --# reserved for compiler pragmas + --# used for compiler pragmas </PRE> <P> A <CODE>concrete</CODE> can be opened like a <CODE>resource</CODE>. @@ -181,7 +184,7 @@ An <CODE>abstract</CODE> can be opened like an <CODE>interface</CODE>. Any <CODE>concrete</CODE> of it then works as an <CODE>instance</CODE>. </P> <A NAME="toc3"></A> -<H2>Judgements</H2> +<H3>Judgements</H3> <PRE> cat C -- declare category C cat C (x:A)(y:B x) -- dependent category C @@ -225,7 +228,7 @@ Judgements can also share RHS: </PRE> <P></P> <A NAME="toc4"></A> -<H2>Types</H2> +<H3>Types</H3> <P> Abstract syntax (in <CODE>fun</CODE>): </P> @@ -259,7 +262,7 @@ Concrete syntax (in <CODE>lincat</CODE>): Resource (in <CODE>oper</CODE>): all those of concrete, plus </P> <PRE> - Tok -- tokens (subset of Str) + Tok -- tokens (subtype of Str) A -> B -- functions from A to B Int -- integers Strs -- list of prefixes (for pre) @@ -268,11 +271,11 @@ Resource (in <CODE>oper</CODE>): all those of concrete, plus </PRE> <P> As parameter types, one can use any finite type: -<CODE>param</CODE> constants <CODE>P</CODE>, +<CODE>P</CODE> defined in <CODE>param P</CODE>, <CODE>Ints n</CODE>, and record types of parameter types. </P> <A NAME="toc5"></A> -<H2>Expressions</H2> +<H3>Expressions</H3> <P> Syntax trees = full function applications </P> @@ -286,7 +289,7 @@ Syntax trees = full function applications Higher-Order Abstract syntax (HOAS): functions as arguments: </P> <PRE> - F a (\y -> b) -- : C if a : A, b : B (x : A), + F a (\x -> c) -- : C if a : A, c : C (x : B), fun F : A -> (B -> C) -> C </PRE> <P> @@ -320,7 +323,7 @@ Tables _ => "mouse" -- wildcard pattern } table { - n => regn n "cat" ;-- variable pattern + n => regn n "cat" -- variable pattern } table Num {...} -- table given with arg. type table ["ox"; "oxen"] -- table as course of values @@ -336,7 +339,6 @@ Records <PRE> {s = "Liz"; g = Fem} -- record in full form {s,t = "et"} -- same as {s = "et";t= "et"} - {s = "Liz"} ** -- record extension: same as {g = Fem} {s = "Liz" ; g = Fem} @@ -392,14 +394,15 @@ Example: </PRE> <P></P> <A NAME="toc6"></A> -<H2>Pattern matching</H2> +<H3>Pattern matching</H3> <P> These patterns can be used in branches of <CODE>table</CODE> and -<CODE>case</CODE> expressions. +<CODE>case</CODE> expressions. Patterns are matched in the order in +which they appear in the grammar. </P> <PRE> C -- atomic param constructor - C p q -- param constr. appl- to patterns + C p q -- param constr. applied to patterns x -- variable, matches anything _ -- wildcard, matches anything "foo" -- string @@ -414,7 +417,7 @@ These patterns can be used in branches of <CODE>table</CODE> and </PRE> <P></P> <A NAME="toc7"></A> -<H2>Sample library functions</H2> +<H3>Sample library functions</H3> <PRE> -- lib/prelude/Predef.gf drop : Int -> Tok -> Tok -- drop prefix of length @@ -446,7 +449,7 @@ These patterns can be used in branches of <CODE>table</CODE> and </PRE> <P></P> <A NAME="toc8"></A> -<H2>Flags</H2> +<H3>Flags</H3> <P> Flags can appear, with growing priority, </P> @@ -480,13 +483,13 @@ Some common flags used in grammars: optimize=noexpand for resource, if =all too big </PRE> <P> -For the full set of values for <CODE>flag</CODE>, -use on-line <CODE>h -flag</CODE>. +For the full set of values for <CODE>FLAG</CODE>, +use on-line <CODE>h -FLAG</CODE>. </P> <A NAME="toc9"></A> -<H2>File paths</H2> +<H3>File paths</H3> <P> -Colon-separated lists of directories tried in the +Colon-separated lists of directories searched in the given order: </P> <PRE> @@ -499,12 +502,12 @@ when invoked, or as flag to the <CODE>i</CODE> command. The prefix <CODE>--#</CODE> is used only in files. </P> <P> -If the variabls <CODE>GF_LIB_PATH</CODE> is defined, its +If the environment variabls <CODE>GF_LIB_PATH</CODE> is defined, its value is automatically prefixed to each directory to extend the original search path. </P> <A NAME="toc10"></A> -<H2>Alternative grammar formats</H2> +<H3>Alternative grammar formats</H3> <P> <B>Old GF</B> (before GF 2.0): all judgements in any kinds of modules, @@ -530,7 +533,7 @@ Rules must be one per line. The RHS can be empty. </PRE> <P> where the RHS is a regular expression of categories -and quoted tokens: <CODE>"foo", T U, T|U, T*, T+, T?</CODE>, or empty. +and quoted tokens: <CODE>"foo", CAT, T U, T|U, T*, T+, T?</CODE>, or empty. Rule labels are generated automatically. </P> <P> @@ -560,7 +563,7 @@ are preprocessed by using a parser given by the flag and the result is written to <CODE>foo.gf</CODE>. </P> <A NAME="toc11"></A> -<H2>References</H2> +<H3>References</H3> <P> <A HREF="http://www.cs.chalmers.se/~aarne/GF/">GF Homepage</A> </P> |
