From 5161a93ae8e728e70eac16087cb83df5436ac8a6 Mon Sep 17 00:00:00 2001 From: aarne Date: Fri, 16 Dec 2005 21:19:32 +0000 Subject: [PATCH] tutorial goes on --- doc/tutorial/gf-tutorial2.html | 380 +++++++++++++++++---------------- doc/tutorial/gf-tutorial2.txt | 125 ++++++----- 2 files changed, 265 insertions(+), 240 deletions(-) diff --git a/doc/tutorial/gf-tutorial2.html b/doc/tutorial/gf-tutorial2.html index d7365d029..a48bcaab6 100644 --- a/doc/tutorial/gf-tutorial2.html +++ b/doc/tutorial/gf-tutorial2.html @@ -7,7 +7,7 @@

Grammatical Framework Tutorial

Author: Aarne Ranta <aarne (at) cs.chalmers.se>
-Last update: Fri Dec 16 21:04:37 2005 +Last update: Fri Dec 16 22:10:53 2005

@@ -18,7 +18,7 @@ Last update: Fri Dec 16 21:04:37 2005 -
  • My first grammar +
  • The ``.cf`` grammar format -
  • The GF grammar format +
  • The ``.gf`` grammar format -
  • Topics still to be written +
  • Multilingual grammars and translation +
  • Grammar architecture + +
  • Resource modules + +
  • Topics still to be written + @@ -109,7 +144,7 @@ To start the GF program, assuming you have installed it, just type in the shell. You will see GF's welcome message and the prompt >.

    -

    My first grammar

    +

    The ``.cf`` grammar format

    Now you are ready to try out your first grammar. We start with one that is not written in GF language, but @@ -260,7 +295,7 @@ generate ten strings with one and the same command:

    Systematic generation

    -To generate <i>all<i> sentence that a grammar +To generate all sentence that a grammar can generate, use the command generate_trees = gt. 

    @@ -301,9 +336,10 @@ want to see:
 
    
 
         > gr -tr | l -tr | p
-    Mks_0 (Mks_7 Mks_10) (Mks_1 Mks_18)
-    a louse sleeps
-    Mks_0 (Mks_7 Mks_10) (Mks_1 Mks_18)
+  
+    S_NP_VP (NP_the_CN CN_snake) (VP_V V_sleeps)
+    the snake sleeps
+    S_NP_VP (NP_the_CN CN_snake) (VP_V V_sleeps)
 
    
 
    
 This facility is good for test purposes: for instance, you
@@ -324,7 +360,7 @@ You can read the file back to GF with the
 read_file = rf command,
 
    
 
    -    > read_file exx.tmp | l -tr | p -lines
+    > read_file exx.tmp | p -lines
 
    
 
    
 Notice the flag -lines given to the parsing
@@ -338,45 +374,51 @@ a sentence but a sequence of ten sentences.
 
    
 The syntax trees returned by GF's parser in the previous examples
 are not so nice to look at. The identifiers of form Mks
-are labels of the EBNF rules. To see which label corresponds to
+are labels of the BNF rules. To see which label corresponds to
 which rule, you can use the print_grammar = pg command
 with the printer flag set to cf (which means context-free):
 
    
 
         > print_grammar -printer=cf
-    Mks_10. CN ::= "louse" ;
-    Mks_11. CN ::= "snake" ;
-    Mks_12. CN ::= "worm" ;
-    Mks_8.  CN ::= A CN ;
-    Mks_9.  CN ::= "boy" ;
-    Mks_4.  NP ::= "this" CN ;
-    Mks_15. A  ::= "thick" ;
+  
+    V_laughs. V ::= "laughs" ;
+    V_sleeps. V ::= "sleeps" ;
+    V_swims. V ::= "swims" ;
+    VP_TV_NP. VP ::= TV NP ;
+    VP_V. VP ::= V ;
+    VP_is_A. VP ::= "is" A ;
+    TV_eats. TV ::= "eats" ;
+    TV_kills. TV ::= "kills" ;
+    TV_washes. TV ::= "washes" ;
+    S_NP_VP. S ::= NP VP ;
+    NP_a_CN. NP ::= "a" ;
     ...
 
    
 
    
 A syntax tree such as
 
    
 
    -    Mks_4 (Mks_8 Mks_15 Mks_12)
+    NP_this_CN (CN_A_CN A_thick CN_worm)
     this thick worm
 
    
 
    
 encodes the sequence of grammar rules used for building the
-expression. If you look at this tree, you will notice that Mks_4
-is the label of the rule prefixing this to a common noun,
-Mks_15 is the label of the adjective thick,
-and so on.
-
    
-
    
-<h4>The labelled context-free format<h4>
+expression. If you look at this tree, you will notice that NP_this_CN
+is the label of the rule prefixing this to a common noun (CN),
+thereby forming a noun phrase (NP).
+A_thick is the label of the adjective thick,
+and so on. These labels are formed automatically when the grammar
+is compiled by GF.
 
    
+
+
    The labelled context-free format
    
 
    
 The labelled context-free grammar format permits user-defined
 labels to each rule.
-GF recognizes files of this format by the suffix
-.cf. It is intermediate between EBNF and full GF format.
-Let us include the following rules in the file
-paleolithic.cf.
+In files with the suffix .cf, you can prefix rules with
+labels that you provide yourself - these may be more useful
+than the automatically generated ones. The following is a possible
+labelling of paleolithic.cf with nicer-looking labels.
 
    
 
         PredVP.  S   ::= NP VP ;
@@ -403,25 +445,10 @@ Let us include the following rules in the file
     Kill.    TV  ::= "kills" 
     Wash.    TV  ::= "washes" ;
 
    
-
    
 
    
-<h4>Using the labelled context-free format<h4>
-
    
-
    
-The GF commands for the .cf format are
-exactly the same as for the .ebnf format.
-Just the syntax trees become nicer to read and
-to remember. Notice that before reading in
-a new grammar in GF you often (but not always,
-as we will see later) have first to give the
-command (empty = e), which removes the
-old grammar from the GF shell state.
+With this grammar, the trees look as follows:
 
    
 
    -    > empty
-  
-    > i paleolithic.cf
-  
     > p "the boy eats a snake"
     PredVP (Def Boy) (ComplTV Eat (Indef Snake))
   
@@ -430,10 +457,10 @@ old grammar from the GF shell state.
     a louse is thick
 
    
 
    
-
-
    The GF grammar format
    
+
+
    The ``.gf`` grammar format
    
 
    
-To see what there really is in GF's shell state when a grammar
+To see what there is in GF's shell state when a grammar
 has been imported, you can give the plain command
 print_grammar = pg.
 
    
@@ -446,15 +473,16 @@ you did not need to write the grammar in that notation, but that the
 GF grammar compiler produced it.
 
    
 
    
-However, we will now start to show how GF's own notation gives you
-much more expressive power than the .cf and .ebnf
-formats. We will introduce the .gf format by presenting
+However, we will now start the demonstration 
+how GF's own notation gives you
+much more expressive power than the .cf
+format. We will introduce the .gf format by presenting
 one more way of defining the same grammar as in
-paleolithic.cf and paleolithic.ebnf.
+paleolithic.cf.
 Then we will show how the full GF grammar format enables you
 to do things that are not possible in the weaker formats.
 
    
-
+
 
    Abstract and concrete syntax
    
 
    
 A GF grammar consists of two main parts:
@@ -482,16 +510,15 @@ is interpreted as the following pair of rules:
 The former rule, with the keyword fun, belongs to the abstract syntax.
 It defines the function
 PredVP which constructs syntax trees of form
-(PredVP <i>x<i> <i>y<i>). 
+(PredVP x y). 
 
    
 
    
 The latter rule, with the keyword lin, belongs to the concrete syntax.
 It defines the linearization function for
-syntax trees of form (PredVP <i>x<i> <i>y<i>). 
-
    
-
    
-<h4>Judgement forms<h4>
+syntax trees of form (PredVP x y). 
 
    
+
+
    Judgement forms
    
 
    
 Rules in a GF grammar are called judgements, and the keywords
 fun and lin are used for distinguishing between two
@@ -543,27 +570,25 @@ judgement forms:
 
    
 We return to the precise meanings of these judgement forms later.
 First we will look at how judgements are grouped into modules, and
-show how the grammar paleolithic.cf is
+show how the paleolithic grammar is
 expressed by using modules and judgements.
 
    
-
    
-<h4>Module types<h4>
-
    
+
+
    Module types
    
 
    
 A GF grammar consists of modules, 
 into which judgements are grouped. The most important
 module forms are
 
    
   
      
-  
    • abstract A = M``, abstract syntax A with judgements in
+  
    • abstract A = M, abstract syntax A with judgements in
   the module body M.
-  
    • concrete C of A = M``, concrete syntax C of the
+  
    • concrete C of A = M, concrete syntax C of the
        abstract syntax A, with judgements in the module body M.
   
    
 
-
    
-<h4>Record types, records, and Strs<h4>
-
    
+
+
    Record types, records, and ``Str``s
    
 
    
 The linearization type of a category is a record type, with
 zero of more fields of different types. The simplest record
@@ -579,8 +604,8 @@ which has one field, with label s and type Str.
 Examples of records of this type are
 
    
 
    -    [s = "foo"}
-    [s = "hello" ++ "world"}
+    {s = "foo"}
+    {s = "hello" ++ "world"}
 
    
 
    
 The type Str is really the type of token lists, but
@@ -589,18 +614,26 @@ denoted by string literals in double quotes.
 
    
 
    
 Whenever a record r of type {s : Str} is given,
-r.s is an object of type Str. This is of course
+r.s is an object of type Str. This is
 a special case of the projection rule, allowing the extraction
-of fields from a record.
+of fields from a record:
 
    
+
      
+
    • if r : { ... p : T ... } then r.p : T
+
    
+
+
+
    An abstract syntax example
    
 
    
-<h4>An abstract syntax example<h4>
-
    
-
    
-Each nonterminal occurring in the grammar paleolithic.cf is
-introduced by a cat judgement. Each
-rule label is introduced by a fun judgement.
+To express the abstract syntax of paleolithic.cf in
+a file Paleolithic.gf, we write two kinds of judgements:
 
    
+
      
+
    • Each category is introduced by a cat judgement.
+
    • Each rule label is introduced by a fun judgement,
+  with the type formed from the nonterminals of the rule.
+
    
+
 
       abstract Paleolithic = {
   cat 
@@ -623,9 +656,8 @@ Notice the use of shorthands permitting the sharing of
 the keyword in subsequent judgements, and of the type
 in subsequent fun judgements.
 
    
-
    
-<h4>A concrete syntax example<h4>
-
    
+
+
    A concrete syntax example
    
 
    
 Each category introduced in Paleolithic.gf is
 given a lincat rule, and each
@@ -663,9 +695,8 @@ apply as in abstract modules.
   }
 
    
 
    
-
    
-<h4>Modules and files<h4>
-
    
+
+
    Modules and files
    
 
    
 Module name + .gf = file name
 
    
@@ -691,9 +722,8 @@ GF source files. When reading a module, GF knows whether
 to use an existing .gfc file or to generate
 a new one, by looking at modification times.
 
    
-
    
-<h4>Multilingual grammar<h4>
-
    
+
+
    Multilingual grammars and translation
    
 
    
 The main advantage of separating abstract from concrete syntax is that
 one abstract syntax can be equipped with many concrete syntaxes.
@@ -705,9 +735,8 @@ translation. Let us buid an Italian concrete syntax for
 Paleolithic and then test the resulting 
 multilingual grammar.
 
    
-
    
-<h4>An Italian concrete syntax<h4>
-
    
+
+
    An Italian concrete syntax
    
 
       concrete PaleolithicIta of Paleolithic = {
   lincat 
@@ -739,9 +768,8 @@ multilingual grammar.
   }
 
    
 
    
-
    
-<h4>Using a multilingual grammar<h4>
-
    
+
+
    Using a multilingual grammar
    
 
    
 Import without first emptying
 
    
@@ -767,9 +795,8 @@ Translate by using a pipe:
     il ragazzo mangia il serpente

    -

    -<h4>Translation quiz<h4> -

    + +

    Translation quiz

    This is a simple language exercise that can be automatically generated from a multilingual grammar. The system generates a set of @@ -802,9 +829,8 @@ file for later use, by the command translation_list = tl

    The number flag gives the number of sentences generated.

    -

    -<h4>The multilingual shell state<h4> -

    + +

    The multilingual shell state

    A GF shell is at any time in a state, which contains a multilingual grammar. One of the concrete @@ -825,9 +851,10 @@ things), you can use the command all concretes : PaleolithicIta PaleolithicEng

    -

    -<h4>Extending a grammar<h4> -

    + +

    Grammar architecture

    + +

    Extending a grammar

    The module system of GF makes it possible to extend a grammar in different ways. The syntax of extension is @@ -856,9 +883,8 @@ be built for concrete syntaxes: The effect of extension is that all of the contents of the extended and extending module are put together.

    -

    -<h4>Multiple inheritance<h4> -

    + +

    Multiple inheritance

    Specialized vocabularies can be represented as small grammars that only do "one thing" each, e.g. @@ -887,9 +913,8 @@ same time: }

    -

    -<h4>Visualizing module structure<h4> -

    + +

    Visualizing module structure

    When you have created all the abstract syntaxes and one set of concrete syntaxes needed for Gatherer, @@ -918,9 +943,8 @@ The command print_multi = pm is used for printing the current multi grammar in various formats, of which the format -printer=graph just shows the module dependencies.

    -

    -<h4>The module structure of GathererEng<h4> -

    + +

    The module structure of ``GathererEng``

    The graph uses

    @@ -934,8 +958,8 @@ The graph uses

    <img src="Gatherer.gif">

    - -

    Resource modules

    + +

    Resource modules

    Suppose we want to say, with the vocabulary included in Paleolithic.gf, things like @@ -946,7 +970,7 @@ Suppose we want to say, with the vocabulary included in

    The new grammatical facility we need are the plural forms -of nouns and verbs (<i>boys, sleep<i>), as opposed to their +of nouns and verbs (boys, sleep), as opposed to their singular forms.

    @@ -969,9 +993,8 @@ To be able to do all this, we need two new judgement forms, a new module form, and a generalizarion of linearization types from strings to more complex types.

    -

    -<h4>Parameters and tables<h4> -

    + +

    Parameters and tables

    We define the parameter type of number in Englisn by using a new form of judgement: @@ -1011,13 +1034,12 @@ operator !. For instance,

    is a selection, whose value is "boys".

    -

    -<h4>Inflection tables, paradigms, and oper definitions<h4> -

    + +

    Inflection tables, paradigms, and ``oper`` definitions

    All English common nouns are inflected in number, most of them in the same way: the plural form is formed from the singular form by adding the -ending <i>s<i>. This rule is an example of +ending s. This rule is an example of a paradigm - a formula telling how the inflection forms of a word are formed.

    @@ -1046,9 +1068,8 @@ the function, and the glueing operator + telling that the string held in the variable x and the ending "s" are written together to form one token.

    -

    -<h4>The resource module type<h4> -

    + +

    The ``resource`` module type

    Parameter and operator definitions do not belong to the abstract syntax. They can be used when defining concrete syntax - but they are not @@ -1080,7 +1101,7 @@ Resource modules can extend other resource modules, in the same way as modules of other types can extend modules of the same type.

    - +

    Opening a ``resource``

    Any number of resource modules can be @@ -1114,9 +1135,8 @@ available through resource grammars, whose users only need to pick the right operations and not to know their implementation details.

    -

    -<h4>Worst-case macros and data abstraction<h4> -

    + +

    Worst-case macros and data abstraction

    Some English nouns, such as louse, are so irregular that it makes little sense to see them as instances of a paradigm. Even @@ -1149,9 +1169,8 @@ interface (i.e. the system of type signatures) that makes it correct to use these functions in concrete modules. In programming terms, Noun is then treated as an abstract datatype.

    -

    -<h4>A system of paradigms using Prelude operations<h4> -

    + +

    A system of paradigms using ``Prelude`` operations

    The regular noun paradigm regNoun can - and should - of course be defined by the worst-case macro mkNoun. In addition, some more noun paradigms @@ -1162,8 +1181,8 @@ could be defined, for instance, sNoun : Str -> Noun = \kiss -> mkNoun kiss (kiss + "es") ;

    -What about nouns like <i>fly<i>, with the plural <i>flies<i>? The already -available solution is to use the so-called "technical stem" <i>fl<i> as +What about nouns like fly, with the plural flies? The already +available solution is to use the so-called "technical stem" fl as argument, and define 

    @@ -1183,9 +1202,8 @@ The operator init belongs to a set of operations in the
 resource module Prelude, which therefore has to be
 opened so that init can be used.
 
    
-
    
-<h4>An intelligent noun paradigm using case expressions<h4>
-
    
+
+
    An intelligent noun paradigm using ``case`` expressions
    
 
    
 It may be hard for the user of a resource morphology to pick the right
 inflection paradigm. A way to help this is to define a more intelligent
@@ -1207,16 +1225,15 @@ these forms are explained in the following section.
 
    
 
    
 The paradigms regNoun does not give the correct forms for
-all nouns. For instance, <i>louse - lice<i> and
-<i>fish - fish<i> must be given by using mkNoun.
-Also the word <i>boy<i> would be inflected incorrectly; to prevent
+all nouns. For instance, louse - lice and
+fish - fish must be given by using mkNoun.
+Also the word boy would be inflected incorrectly; to prevent
 this, either use mkNoun or modify 
 regNoun so that the "y" case does not
 apply if the second-last character is a vowel.
 
    
-
    
-<h4>Pattern matching<h4>
-
    
+
+
    Pattern matching
    
 
    
 Expressions of the table form are built from lists of
 argument-value pairs. These pairs are called the branches
@@ -1251,9 +1268,8 @@ programming languages are syntactic sugar for table selections:
     case e of {...} ===  table {...} ! e

    -

    -<h4>Morphological analysis and morphology quiz<h4> -

    + +

    Morphological analysis and morphology quiz

    Even though in GF morphology is mostly seen as an auxiliary of syntax, a morphology once defined @@ -1292,14 +1308,13 @@ file for later use, by the command morpho_list = ml

    The number flag gives the number of exercises generated.

    -

    -<h4>Parametric vs. inherent features, agreement<h4> -

    + +

    Parametric vs. inherent features, agreement

    The rule of subject-verb agreement in English says that the verb phrase must be inflected in the number of the subject. This means that a noun phrase (functioning as a subject), in some sense -<i>has<i> a number, which it "sends" to the verb. The verb does not +has a number, which it "sends" to the verb. The verb does not have a number, but must be able to receive whatever number the subject has. This distinction is nicely represented by the different linearization types of noun phrases and verb phrases: @@ -1329,9 +1344,8 @@ regular only in the present tensse). The reader is invited to inspect the way in which agreement works in the formation of noun phrases and verb phrases.

    -

    -<h4>English concrete syntax with parameters<h4> -

    + +

    English concrete syntax with parameters

       concrete PaleolithicEng of Paleolithic = open MorphoEng in {
   lincat 
@@ -1358,9 +1372,8 @@ the formation of noun phrases and verb phrases.
   }

    -

    -<h4>Hierarchic parameter types<h4> -

    + +

    Hierarchic parameter types

    The reader familiar with a functional programming language such as <a href="http://www.haskell.org">Haskell<a> must have noticed the similarity @@ -1401,15 +1414,14 @@ the adjectival paradigm in which the two singular forms are the same, can be def }

    -

    -<h4>Discontinuous constituents<h4> -

    + +

    Discontinuous constituents

    A linearization type may contain more strings than one. An example of where this is useful are English particle -verbs, such as <i>switch off<i>. The linearization of +verbs, such as switch off. The linearization of a sentence may place the object between the verb and the particle: -<i>he switched it off<i>. +he switched it off.

    The first of the following judgements defines transitive verbs as a @@ -1427,27 +1439,27 @@ GF currently requires that all fields in linearization records that have a table with value type Str have as labels either s or s with an integer index.

    - +

    Topics still to be written

    - +

    Free variation

    - +

    Record extension, tuples

    - +

    Predefined types and operations

    - +

    Lexers and unlexers

    - +

    Grammars of formal languages

    - +

    Resource grammars and their reuse

    - +

    Embedded grammars in Haskell, Java, and Prolog

    - +

    Dependent types, variable bindings, semantic definitions

    - +

    Transfer modules

    - +

    Alternative input and output grammar formats

    diff --git a/doc/tutorial/gf-tutorial2.txt b/doc/tutorial/gf-tutorial2.txt index 3286cfcc9..68a31bd45 100644 --- a/doc/tutorial/gf-tutorial2.txt +++ b/doc/tutorial/gf-tutorial2.txt @@ -66,7 +66,7 @@ in the shell. You will see GF's welcome message and the prompt ``>``. %--! -==My first grammar== +==The ``.cf`` grammar format== Now you are ready to try out your first grammar. We start with one that is not written in GF language, but @@ -200,7 +200,7 @@ generate ten strings with one and the same command: %--! ===Systematic generation=== -To generate all sentence that a grammar +To generate //all// sentence that a grammar can generate, use the command ``generate_trees = gt``. ``` > generate_trees | l @@ -243,7 +243,7 @@ want to see: S_NP_VP (NP_the_CN CN_snake) (VP_V V_sleeps) the snake sleeps S_NP_VP (NP_the_CN CN_snake) (VP_V V_sleeps) - +``` This facility is good for test purposes: for instance, you may want to see if a grammar is **ambiguous**, i.e. contains strings that can be parsed in more than one way. @@ -310,7 +310,7 @@ is compiled by GF. %--! -

    The labelled context-free format

    +===The labelled context-free format=== The **labelled context-free grammar** format permits user-defined labels to each rule. @@ -355,9 +355,9 @@ With this grammar, the trees look as follows: %--! -==The GF grammar format== +==The ``.gf`` grammar format== -To see what there really is in GF's shell state when a grammar +To see what there is in GF's shell state when a grammar has been imported, you can give the plain command ``print_grammar = pg``. ``` @@ -402,17 +402,17 @@ is interpreted as the following pair of rules: The former rule, with the keyword ``fun``, belongs to the abstract syntax. It defines the **function** ``PredVP`` which constructs syntax trees of form -(``PredVP`` x y). +(``PredVP`` //x// //y//). The latter rule, with the keyword ``lin``, belongs to the concrete syntax. It defines the **linearization function** for -syntax trees of form (``PredVP`` x y). +syntax trees of form (``PredVP`` //x// //y//). %--! -

    Judgement forms

    +===Judgement forms=== Rules in a GF grammar are called **judgements**, and the keywords ``fun`` and ``lin`` are used for distinguishing between two @@ -435,26 +435,26 @@ judgement forms: We return to the precise meanings of these judgement forms later. First we will look at how judgements are grouped into modules, and -show how the grammar ``paleolithic.cf`` is +show how the paleolithic grammar is expressed by using modules and judgements. %--! -

    Module types

    +===Module types=== A GF grammar consists of **modules**, into which judgements are grouped. The most important module forms are - - ``abstract`` A = M``, abstract syntax A with judgements in + - ``abstract`` A ``=`` M, abstract syntax A with judgements in the module body M. - - ``concrete`` C ``of`` A = M``, concrete syntax C of the + - ``concrete`` C ``of`` A ``=`` M, concrete syntax C of the abstract syntax A, with judgements in the module body M. %--! -

    Record types, records, and ``Str``s

    +===Record types, records, and ``Str``s=== The linearization type of a category is a **record type**, with zero of more **fields** of different types. The simplest record @@ -468,8 +468,8 @@ which has one field, with **label** ``s`` and type ``Str``. Examples of records of this type are ``` - [s = "foo"} - [s = "hello" ++ "world"} + {s = "foo"} + {s = "hello" ++ "world"} ``` The type ``Str`` is really the type of **token lists**, but most of the time one can conveniently think of it as the type of strings, @@ -478,17 +478,24 @@ denoted by string literals in double quotes. Whenever a record ``r`` of type ``{s : Str}`` is given, -``r.s`` is an object of type ``Str``. This is of course +``r.s`` is an object of type ``Str``. This is a special case of the **projection** rule, allowing the extraction -of fields from a record. +of fields from a record: + +- if //r// : ``{`` ... //p// : //T// ... ``}`` then //r.p// : //T// %--! -

    An abstract syntax example

    +===An abstract syntax example=== + +To express the abstract syntax of ``paleolithic.cf`` in +a file ``Paleolithic.gf``, we write two kinds of judgements: + +- Each category is introduced by a ``cat`` judgement. +- Each rule label is introduced by a ``fun`` judgement, + with the type formed from the nonterminals of the rule. + -Each nonterminal occurring in the grammar ``paleolithic.cf`` is -introduced by a ``cat`` judgement. Each -rule label is introduced by a ``fun`` judgement. ``` abstract Paleolithic = { cat @@ -512,7 +519,7 @@ in subsequent ``fun`` judgements. %--! -

    A concrete syntax example

    +===A concrete syntax example=== Each category introduced in ``Paleolithic.gf`` is given a ``lincat`` rule, and each @@ -551,7 +558,7 @@ lin %--! -

    Modules and files

    +===Modules and files=== Module name + ``.gf`` = file name @@ -581,7 +588,7 @@ a new one, by looking at modification times. %--! -

    Multilingual grammar

    +==Multilingual grammars and translation== The main advantage of separating abstract from concrete syntax is that one abstract syntax can be equipped with many concrete syntaxes. @@ -598,7 +605,7 @@ multilingual grammar. %--! -

    An Italian concrete syntax

    +===An Italian concrete syntax=== ``` concrete PaleolithicIta of Paleolithic = { @@ -632,7 +639,7 @@ lin ``` %--! -

    Using a multilingual grammar

    +===Using a multilingual grammar=== Import without first emptying ``` @@ -656,7 +663,7 @@ Translate by using a pipe: %--! -

    Translation quiz

    +===Translation quiz=== This is a simple language exercise that can be automatically generated from a multilingual grammar. The system generates a set of @@ -687,7 +694,7 @@ The number flag gives the number of sentences generated. %--! -

    The multilingual shell state

    +===The multilingual shell state=== A GF shell is at any time in a state, which contains a multilingual grammar. One of the concrete @@ -710,7 +717,9 @@ things), you can use the command %--! -

    Extending a grammar

    +==Grammar architecture== + +===Extending a grammar=== The module system of GF makes it possible to **extend** a grammar in different ways. The syntax of extension is @@ -738,7 +747,7 @@ and extending module are put together. %--! -

    Multiple inheritance

    +===Multiple inheritance=== Specialized vocabularies can be represented as small grammars that only do "one thing" each, e.g. @@ -767,7 +776,7 @@ same time: %--! -

    Visualizing module structure

    +===Visualizing module structure=== When you have created all the abstract syntaxes and one set of concrete syntaxes needed for ``Gatherer``, @@ -795,7 +804,7 @@ shows the module dependencies. %--! -

    The module structure of ``GathererEng``

    +===The module structure of ``GathererEng``=== The graph uses @@ -811,7 +820,7 @@ The graph uses %--! -===Resource modules=== +==Resource modules== Suppose we want to say, with the vocabulary included in ``Paleolithic.gf``, things like @@ -820,7 +829,7 @@ Suppose we want to say, with the vocabulary included in all boys sleep ``` The new grammatical facility we need are the plural forms -of nouns and verbs (boys, sleep), as opposed to their +of nouns and verbs (//boys, sleep//), as opposed to their singular forms. @@ -846,7 +855,7 @@ from strings to more complex types. %--! -

    Parameters and tables

    +===Parameters and tables=== We define the **parameter type** of number in Englisn by using a new form of judgement: @@ -880,11 +889,11 @@ is a selection, whose value is ``"boys"``. %--! -

    Inflection tables, paradigms, and ``oper`` definitions

    +===Inflection tables, paradigms, and ``oper`` definitions=== All English common nouns are inflected in number, most of them in the same way: the plural form is formed from the singular form by adding the -ending s. This rule is an example of +ending //s//. This rule is an example of a **paradigm** - a formula telling how the inflection forms of a word are formed. @@ -914,7 +923,7 @@ are written together to form one **token**. %--! -

    The ``resource`` module type

    +===The ``resource`` module type=== Parameter and operator definitions do not belong to the abstract syntax. They can be used when defining concrete syntax - but they are not @@ -983,7 +992,7 @@ details. %--! -

    Worst-case macros and data abstraction

    +===Worst-case macros and data abstraction=== Some English nouns, such as ``louse``, are so irregular that it makes little sense to see them as instances of a paradigm. Even @@ -1016,7 +1025,7 @@ terms, ``Noun`` is then treated as an **abstract datatype**. %--! -

    A system of paradigms using ``Prelude`` operations

    +===A system of paradigms using ``Prelude`` operations=== The regular noun paradigm ``regNoun`` can - and should - of course be defined by the worst-case macro ``mkNoun``. In addition, some more noun paradigms @@ -1025,8 +1034,8 @@ could be defined, for instance, regNoun : Str -> Noun = \snake -> mkNoun snake (snake + "s") ; sNoun : Str -> Noun = \kiss -> mkNoun kiss (kiss + "es") ; ``` -What about nouns like fly, with the plural flies? The already -available solution is to use the so-called "technical stem" fl as +What about nouns like //fly//, with the plural //flies//? The already +available solution is to use the so-called "technical stem" //fl// as argument, and define ``` yNoun : Str -> Noun = \fl -> mkNoun (fl + "y") (fl + "ies") ; @@ -1045,7 +1054,7 @@ resource module ``Prelude``, which therefore has to be %--! -

    An intelligent noun paradigm using ``case`` expressions

    +===An intelligent noun paradigm using ``case`` expressions=== It may be hard for the user of a resource morphology to pick the right inflection paradigm. A way to help this is to define a more intelligent @@ -1066,9 +1075,9 @@ these forms are explained in the following section. The paradigms ``regNoun`` does not give the correct forms for -all nouns. For instance, louse - lice and -fish - fish must be given by using ``mkNoun``. -Also the word boy would be inflected incorrectly; to prevent +all nouns. For instance, //louse - lice// and +//fish - fish// must be given by using ``mkNoun``. +Also the word //boy// would be inflected incorrectly; to prevent this, either use ``mkNoun`` or modify ``regNoun`` so that the ``"y"`` case does not apply if the second-last character is a vowel. @@ -1076,7 +1085,7 @@ apply if the second-last character is a vowel. %--! -

    Pattern matching

    +===Pattern matching=== Expressions of the ``table`` form are built from lists of argument-value pairs. These pairs are called the **branches** @@ -1111,7 +1120,7 @@ programming languages are syntactic sugar for table selections: %--! -

    Morphological analysis and morphology quiz

    +===Morphological analysis and morphology quiz=== Even though in GF morphology is mostly seen as an auxiliary of syntax, a morphology once defined @@ -1147,12 +1156,12 @@ The number flag gives the number of exercises generated. %--! -

    Parametric vs. inherent features, agreement

    +===Parametric vs. inherent features, agreement=== The rule of subject-verb agreement in English says that the verb phrase must be inflected in the number of the subject. This means that a noun phrase (functioning as a subject), in some sense -has a number, which it "sends" to the verb. The verb does not +//has// a number, which it "sends" to the verb. The verb does not have a number, but must be able to receive whatever number the subject has. This distinction is nicely represented by the different linearization types of noun phrases and verb phrases: @@ -1182,7 +1191,7 @@ the formation of noun phrases and verb phrases. %--! -

    English concrete syntax with parameters

    +===English concrete syntax with parameters=== ``` concrete PaleolithicEng of Paleolithic = open MorphoEng in { @@ -1213,7 +1222,7 @@ lin %--! -

    Hierarchic parameter types

    +===Hierarchic parameter types=== The reader familiar with a functional programming language such as Haskell must have noticed the similarity @@ -1255,13 +1264,13 @@ the adjectival paradigm in which the two singular forms are the same, can be def %--! -

    Discontinuous constituents

    +===Discontinuous constituents=== A linearization type may contain more strings than one. An example of where this is useful are English particle -verbs, such as switch off. The linearization of +verbs, such as //switch off//. The linearization of a sentence may place the object between the verb and the particle: -he switched it off. +//he switched it off//. @@ -1311,6 +1320,10 @@ either ``s`` or ``s`` with an integer index. +===Speech input and output=== + + + ===Embedded grammars in Haskell, Java, and Prolog===