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diff --git a/doc/gf-refman.html b/doc/gf-refman.html index 188a063a8..376689a9a 100644 --- a/doc/gf-refman.html +++ b/doc/gf-refman.html @@ -5,7 +5,7 @@ </HEAD><BODY BGCOLOR="white" TEXT="black"> <P ALIGN="center"><CENTER><H1>GF Language Reference Manual</H1> <FONT SIZE="4"> -<I>Aarne Ranta</I><BR>February 2008 +<I>Aarne Ranta</I>, <I>Krasimir Angelov</I><BR>November 2013 </FONT></CENTER> <P></P> @@ -39,6 +39,7 @@ <LI><A HREF="#toc22">Linearization type definitions, lincat</A> <LI><A HREF="#toc23">Linearization definitions, lin</A> <LI><A HREF="#toc24">Linearization default definitions, lindef</A> + <LI><A HREF="#toc24_r">Linearization reference definitions, linref</A> <LI><A HREF="#toc25">Printname definitions, printname cat and printname fun</A> <LI><A HREF="#toc26">Parameter type definitions, param</A> <LI><A HREF="#toc27">Parameter values</A> @@ -968,8 +969,15 @@ name to the scope. <TD>yes</TD> </TR> <TR> -<TD><CODE>lindef</CODE> f = t</TD> -<TD>f fun, t term</TD> +<TD><CODE>lindef</CODE> C = t</TD> +<TD>C cat, t term</TD> +<TD>concrete*</TD> +<TD>yes</TD> +<TD>no</TD> +</TR> +<TR> +<TD><CODE>linref</CODE> C = t</TD> +<TD>C cat, t term</TD> <TD>concrete*</TD> <TD>yes</TD> <TD>no</TD> @@ -1355,11 +1363,17 @@ type of <I>C</I>. Linearization defaults are invoked when linearizing variable bindings in higher-order abstract syntax. A variable symbol is then presented as a string, which must be converted to correct type in order for -linearization not to fail with an error. +the linearization not to fail with an error. </P> <P> -The defaults can also be used for linearizing metavariables -in an interactive syntax editor. +The other use of the defaults is for linearizing metavariables +and abstract functions without linearization in the concrete syntax. +In the first case the default linearization is applied to +the string <CODE>"?X"</CODE> where <CODE>X</CODE> is the unique index +of the metavariable, and in the second case the string is +<CODE>"[f]"</CODE> where <CODE>f</CODE> is the name of the abstract +function with missing linearization. + </P> <P> Usually, linearization defaults are generated by using the default @@ -1376,8 +1390,62 @@ definition is by structural recursion on the type: <P> The notion of the first value of a parameter type (#1(P)) is defined -<a href="#paramvalues">here</a> below. +<a href="#paramvalues">below</a>. </P> +<A NAME="toc24_r"></A> +<H3>Linearization reference definitions, linref</H3> +<P> +<a name="linrefjudgements"></a> +</P> +<P> +A linearization reference definition, +<center> + <CODE>linref</CODE> <I>C</I> <CODE>=</CODE> <I>t</I> +</center> +defines the reference linearization of category <I>C</I>, i.e. the function +applicable to an object of the linearization type of <I>C</I> to make it into a string. +</P> +<P> +The reference linearization is always applied to the top-level node +of the abstract syntax tree. For example when we linearize the +tree <CODE>f x1 x2 .. xn</CODE>, then we first apply <CODE>f</CODE> +to its arguments which gives us an object of the linearization type of +its category. After that we apply the reference linearization +for the same category to get a string out of the object. This +is particularly useful when the linearization type of <I>C</I> +contains discontious constituents. In this case usually the reference +linearization glues the constituents together to produce an +intuitive linearization string. +</P> +<P> +The reference linearization is also used for linearizing metavariables +which stand in function position. For example the tree +<CODE>f (? x1 x2 .. xn)</CODE> is linearized as follows. Each +of the arguments <CODE>x1 x2 .. xn</CODE> is linearized, and after that +the reference linearization of the its category is applied +to the output of the linearization. The result is a sequence of <CODE>n</CODE> +strings which are concatenated into a single string. The final string +is the input to the default linearization of the category +for the argument of <CODE>f</CODE>. After applying the default linearization +we get an object that we could safely pass to <CODE>f</CODE>. +</P> +<P> +Usually, linearization references are generated by using the +rule that "picks the first string in the linearization type". The precise +definition is by structural recursion on the type: +</P> +<UL> +<LI>reference(Str,o) = Just o +<LI>reference(P,s) = Nothing +<LI>reference(P => T,o) = reference(T,o ! #1(P)) || reference(T,o ! #2(P)) || ... || reference(T,o ! #n(P)) +<LI>reference({r1 : R1; ... rn : Rn},o) = reference(R1, o.r1) || reference(R2, o.r2) || ... || reference(Rn, o.rn) +</UL> +Here each call to reference returns either <CODE>(Just o)</CODE> or <CODE>Nothing</CODE>. +When we compute the reference for a table or a record then we pick +the reference for the first expression for which the recursive call +gives us <CODE>Just</CODE>. If we get <CODE>Nothing</CODE> for +all of them then the final result is <CODE>Nothing</CODE> too. + <A NAME="toc25"></A> <H3>Printname definitions, printname cat and printname fun</H3> <P> @@ -2927,7 +2995,7 @@ literals). <H3>Predefined concrete syntax operations</H3> <P> The following predefined operations are defined in the resource module -<CODE>prelude/Predefined.gf</CODE>. Their implementations are defined as +<CODE>prelude/Predef.gf</CODE>. Their implementations are defined as a part of the GF grammar compiler. </P> <TABLE ALIGN="center" CELLPADDING="4" BORDER="1"> @@ -3031,6 +3099,26 @@ a part of the GF grammar compiler. <TD><CODE>(L : Type) -> L -> Str</CODE></TD> <TD>find the "first" string</TD> </TR> +<TR> +<TD><CODE>nonExist</CODE></TD> +<TD><CODE>Str</CODE></TD> +<TD>this is a special token marking<BR/> +non-existing morphological forms</TD> +</TR> +<TR> +<TD><CODE>BIND</CODE></TD> +<TD><CODE>Str</CODE></TD> +<TD>this is a special token marking<BR/> +that the surrounding tokens should not<BR/> +be separated by space</TD> +</TR> +<TR> +<TD><CODE>SOFT_BIND</CODE></TD> +<TD><CODE>Str</CODE></TD> +<TD>this is a special token marking<BR/> +that the surrounding tokens may not<BR/> +be separated by space</TD> +</TR> </TABLE> <P></P> @@ -3427,24 +3515,25 @@ The reserved words used in GF are the following: <TD><CODE>lindef</CODE></TD> </TR> <TR> +<TD><CODE>linref</CODE></TD> <TD><CODE>of</CODE></TD> <TD><CODE>open</CODE></TD> <TD><CODE>oper</CODE></TD> -<TD><CODE>param</CODE></TD> </TR> <TR> +<TD><CODE>param</CODE></TD> <TD><CODE>pre</CODE></TD> <TD><CODE>printname</CODE></TD> <TD><CODE>resource</CODE></TD> -<TD><CODE>strs</CODE></TD> </TR> <TR> +<TD><CODE>strs</CODE></TD> <TD><CODE>table</CODE></TD> <TD><CODE>transfer</CODE></TD> <TD><CODE>variants</CODE></TD> -<TD><CODE>where</CODE></TD> </TR> <TR> +<TD><CODE>where</CODE></TD> <TD><CODE>with</CODE></TD> <TD></TD> <TD></TD> @@ -3773,6 +3862,11 @@ All other symbols are terminals. <TR> <TD></TD> <TD ALIGN="center"><B>|</B></TD> +<TD><CODE>linref</CODE> <I>[Def]</I></TD> +</TR> +<TR> +<TD></TD> +<TD ALIGN="center"><B>|</B></TD> <TD><CODE>lin</CODE> <I>[Def]</I></TD> </TR> <TR> |