Update asn1 documentation

Language cleaned up by the technical writers xsipewe and tmanevik
from Combitech. Proofreading and corrections by Björn Gustavsson.

1 files changed, 272 insertions, 249 deletions

diff --git a/lib/asn1/doc/src/asn1_spec.xmlsrc b/lib/asn1/doc/src/asn1_spec.xmlsrc
index 9001aca65c..5bee9f0075 100644
--- a/lib/asn1/doc/src/asn1_spec.xmlsrc
+++ b/lib/asn1/doc/src/asn1_spec.xmlsrc
@@ -29,94 +29,105 @@
     <file>asn1_spec.xml</file>
   </header>
   <marker id="SpecializedDecodes"></marker>
-  <p>When performance is of highest priority and one is interested in
-    a limited part of the ASN.1 encoded message, before one decide what
-    to do with the rest of it, one may want to decode only this small
-    part. The situation may be a server that has to decide to which
-    addressee it will send a message. The addressee may be interested in
-    the entire message, but the server may be a bottleneck that one want
-    to spare any unnecessary load. Instead of making two <em>complete decodes</em> (the normal case of decode), one in the server and one
-    in the addressee, it is only necessary to make one <em>specialized decode</em>(in the server) and another complete decode(in the
-    addressee). The following specialized decodes <em>exclusive decode</em> and <em>selected decode</em> support to solve this and
-    similar problems.
-    </p>
+  <p>When performance is of highest priority and you are interested in
+    a limited part of the ASN.1 encoded message before deciding what
+    to do with the rest of it, an option is to decode only this small
+    part. The situation can be a server that has to decide the
+    addressee of a message. The addressee can be interested in
+    the entire message, but the server can be a bottleneck that you want
+    to spare any unnecessary load.</p>
+  <p> Instead of making two <em>complete decodes</em> (the normal case of
+    decode), one in the server and one in the addressee, it is only
+    necessary to make one <em>specialized decode</em>(in the server)
+    and another complete decode(in the addressee). This section
+    describes the following two specialized decodes, which support
+    to solve this and similar problems:</p>
+    <list type="bulleted">
+      <item><em>Exclusive decode</em></item>
+      <item><em>Selected decode</em></item>
+    </list>
   <p>So far this functionality is only provided when using the
-    optimized BER_BIN version, that is when compiling with the
-    options <c>ber_bin</c> and <c>optimize</c>. It does also work
-    using the <c>nif</c> option. We have no intent to make this
-    available on the default BER version, but maybe in the PER_BIN
-    version (<c>per_bin</c>).
+    optimized <c>BER_BIN</c> version, that is, when compiling with
+    options <c>ber_bin</c> and <c>optimize</c>. It also works
+    with option<c>nif</c>. We do not intent to make this functionality
+    available in the default <c>BER</c> version, but possibly in the
+    <c>PER_BIN</c> version (<c>per_bin</c>).
     </p>
 
   <section>
     <title>Exclusive Decode</title>
     <p>The basic idea with exclusive
-      decode is that you specify which parts of the message you want to
+      decode is to specify which parts of the message you want to
       exclude from being decoded. These parts remain encoded and are
-      returned in the value structure as binaries. They may be decoded
+      returned in the value structure as binaries. They can be decoded
       in turn by passing them to a certain <c>decode_part/2</c>
-      function. The performance gain is high when the message is large
-      and you can do an exclusive decode and later on one or several
-      decodes of the parts or a second complete decode instead of two or
+      function. The performance gain is high for large messages.
+      You can do an exclusive decode and later one or more
+      decodes of the parts, or a second complete decode instead of two or
       more complete decodes.
       </p>
 
     <section>
-      <title>How To Make It Work</title>
-      <p>In order to make exclusive decode work you have to do the
-        following:
+      <title>Procedure</title>
+      <p>To perform an exclusive decode:
         </p>
       <list type="bulleted">
-        <item>First,decide the name of the function for the exclusive
-         decode.</item>
-        <item>Second, write instructions that must consist of the name
-         of the exclusive decode function, the name of the ASN.1
-         specification and a notation that tells which parts of the
-         message structure will be excluded from decode. These
-         instructions shall be included in a configuration
-         file. </item>
-        <item>Third, compile with the additional option
-        <c>asn1config</c>. The compiler searches for a configuration
-         file with the same name as the ASN.1 spec but with the
-         extension .asn1config. This configuration file is not the same
-         as used for compilation of a set of files. See section
-        <seealso marker="#UndecodedPart">Writing an Exclusive Decode Instruction.</seealso></item>
+        <item><em>Step 1:</em> Decide the name of the function for the
+	 exclusive decode.</item>
+        <item><p><em>Step 2:</em> Include the following instructions in
+	 a configuration file:</p>
+	 <list type="bulleted">
+	   <item>The name of the exclusive decode function</item>
+	   <item>The name of the ASN.1 specification</item>
+	   <item>A notation that tells which parts of the message
+	   structure to be excluded from decode</item>
+	   </list></item>
+        <item><em>Step 3</em> Compile with the additional option
+         <c>asn1config</c>. The compiler searches for a configuration
+         file with the same name as the ASN.1 specification but with
+         extension <c>.asn1config</c>. This configuration file is not
+	 the same as used for compilation of a set of files. See Section
+	 <seealso marker="#UndecodedPart">Writing an Exclusive Decode
+	 Instruction.</seealso></item>
       </list>
     </section>
 
     <section>
       <title>User Interface</title>
-      <p>The run-time user interface for exclusive decode consists of
-        two different functions. First, the function for an exclusive
-        decode, whose name the user decides in the configuration
-        file. Second, the compiler generates a <c>decode_part/2</c>
-        function when exclusive decode is chosen. This function decodes
-        the parts that were left undecoded during the exclusive
-        decode. Both functions are described below.
-        </p>
-      <p>If the exclusive decode function has for example got the name
+      <p>The runtime user interface for exclusive decode consists of
+        the following two functions:</p>
+	<list type="bulleted">
+	  <item>A function for an exclusive decode, whose name the user
+	  decides in the configuration file</item>
+	  <item>The compiler generates a <c>decode_part/2</c>
+          function when exclusive decode is chosen. This function decodes
+          the parts that were left undecoded during the exclusive
+          decode.</item>
+	</list>
+      <p>Both functions are described in the following.</p>
+      <p>If the exclusive decode function has, for example, the name
         <c>decode_exclusive</c> and an ASN.1 encoded message
-        <c>Bin</c> shall be exclusive decoded, the call is:</p>
+        <c>Bin</c> is to be exclusive decoded, the call is as follows:</p>
       <pre>
 {ok,Excl_Message} = 'MyModule':decode_exclusive(Bin)      </pre>
       <marker id="UndecodedPart"></marker>
-      <p>The result <c>Excl_Message</c> has the same structure as an
-        complete decode would have, except for the parts of the top-type
-        that were not decoded. The undecoded parts will be on their place
-        in the structure on the format <c>{Type_Key,Undecoded_Value}</c>.
+      <p>The result <c>Excl_Message</c> has the same structure as a
+        complete decode would have, except for the parts of the top type
+        that were not decoded. The undecoded parts are on their places
+        in the structure on format <c>{Type_Key,Undecoded_Value}</c>.
         </p>
-      <p>Each undecoded part that shall be decoded must be fed into the <c>decode_part/2</c> function,like:</p>
+      <p>Each undecoded part that is to be decoded must be fed into
+        function <c>decode_part/2</c> as follows:</p>
       <pre>
-{ok,Part_Message} = 'MyModule':decode_part(Type_Key,Undecoded_Value)      </pre>
+{ok,Part_Message} = 'MyModule':decode_part(Type_Key,Undecoded_Value)</pre>
     </section>
 
     <section>
       <marker id="Exclusive Instruction"></marker>
       <title>Writing an Exclusive Decode Instruction</title>
-      <p>This instruction is written in the configuration file on the
-        format:</p>
+      <p>This instruction is written in the configuration file
+        in the following format:</p>
       <pre>
-
 Exclusive_Decode_Instruction = {exclusive_decode,{Module_Name,Decode_Instructions}}.
 
 Module_Name = atom()
@@ -137,70 +148,76 @@ Element = {Name,parts} |
 
 Top_Type = atom()
 
-Name = atom()
-      </pre>
-      <p>Observe that the instruction must be a valid Erlang term ended
-        by a dot.
+Name = atom()</pre>
+      <p>The instruction must be a valid Erlang term ended by a dot.
         </p>
-      <p>In the <c>Type_List</c> the "path" from the top type to each
-        undecoded sub-components is described. The top type of the path is
+      <p>In <c>Type_List</c> the "path" from the top type to each
+        undecoded subcomponents is described. The top type of the path is
         an atom, the name of it. The action on each component/type that
-        follows will be described by one of <c>{Name,parts}, {Name,undecoded}, {Name,Element_List}</c></p>
-      <p>The use and effect of the actions are:
+        follows is described by one of
+        <c>{Name,parts}, {Name,undecoded}, {Name,Element_List}</c>.</p>
+      <p>The use and effect of the actions are as follows:
         </p>
       <list type="bulleted">
-        <item><c>{Name,undecoded}</c> Tells that the element will be
-         left undecoded during the exclusive decode. The type of Name may
-         be any ASN.1 type. The value of element Name will be returned as a
-         tuple,as mentioned <seealso marker="#UndecodedPart">above</seealso>, in the value structure of the top type.</item>
-        <item><c>{Name,parts}</c> The type of Name may be one of
-         SEQUENCE OF or SET OF. The action implies that the different
-         components of Name will be left undecoded. The value of Name
-         will be returned as a tuple, as <seealso marker="#UndecodedPart">above </seealso>, where the second element is a list of
-         binaries. That is because the representation of a SEQUENCE OF/
-         SET OF in Erlang is a list of its internal type. Any of the
-         elements of this list or the entire list can be decoded by the
-        <c>decode_part</c> function.</item>
-        <item><c>{Name,Element_List}</c>This action is used when one or
-         more of the sub-types of Name will be exclusive decoded.</item>
+        <item><c>{Name,undecoded}</c> - Tells that the element is left
+         undecoded during the exclusive decode. The type of <c>Name</c>
+         can be any ASN.1 type. The value of element <c>Name</c> is
+         returned as a tuple (as mentioned in the previous section) in
+         the value structure of the top type.</item>
+        <item><c>{Name,parts}</c> - The type of <c>Name</c> can be one of
+         <c>SEQUENCE OF</c> or <c>SET OF</c>. The action implies that
+         the different components of <c>Name</c> are left undecoded. The
+         value of <c>Name</c> is returned as a tuple (as mentioned in
+         the previous section) where the second element is a list of
+         binaries. This is because the representation of a <c>SEQUENCE OF</c>
+         or a <c>SET OF</c> in Erlang is a list of its internal type. Any
+         of the elements in this list or the entire list can be decoded by
+         function <c>decode_part</c>.</item>
+        <item><c>{Name,Element_List}</c> - This action is used when one or
+         more of the subtypes of <c>Name</c> is exclusive decoded.</item>
       </list>
-      <p>Name in the actions above may be a component name of a
-        SEQUENCE or a SET or a name of an alternative in a CHOICE.
+      <p><c>Name</c> in these actions can be a component name of a
+        <c>SEQUENCE OF</c> or a <c>SET OF</c>, or a name of an alternative
+         in a <c>CHOICE</c>.
         </p>
     </section>
 
     <section>
       <title>Example</title>
-      <p>In the examples below we use the definitions from the following ASN.1 spec:</p>
+      <p>In this examples, the definitions from the following ASN.1
+        specification are used:</p>
       <marker id="Asn1spec"></marker>
       <codeinclude file="Seq.asn" tag="" type="none"></codeinclude>
-      <p>If <c>Button</c> is a top type and we want to exclude
-        component <c>number</c> from decode the Type_List in the
-        instruction in the configuration file will be
-        <c>['Button',[{number,undecoded}]]</c>. If we call the decode
-        function <c>decode_Button_exclusive</c> the Decode_Instruction
-        will be
+      <p>If <c>Button</c> is a top type and it is needed to exclude
+        component <c>number</c> from decode, <c>Type_List</c> in the
+        instruction in the configuration file is
+        <c>['Button',[{number,undecoded}]]</c>. If you call the decode
+        function <c>decode_Button_exclusive</c>, <c>Decode_Instruction</c> is
         <c>{decode_Button_exclusive,['Button',[{number,undecoded}]]}</c>.
         </p>
-      <p>We also have another top type <c>Window</c> whose sub
-        component actions in type <c>Status</c> and the parts of component
-        <c>buttonList</c> shall be left undecoded. For this type we name
-        the function <c>decode__Window_exclusive</c>. The whole
-        Exclusive_Decode_Instruction configuration is as follows: </p>
+      <p>Another top type is <c>Window</c> whose subcomponent
+        actions in type <c>Status</c> and the parts of component
+        <c>buttonList</c> are to be left undecoded. For this type, the
+        function is named <c>decode__Window_exclusive</c>. The complete
+        <c>Exclusive_Decode_Instruction</c> configuration is as follows:</p>
       <codeinclude file="Seq.asn1config" tag="" type="none"></codeinclude>
+      <p>The following figure shows the bytes of a <c>Window:status</c>
+        message. The components <c>buttonList</c> and <c>actions</c> are
+	excluded from decode. Only <c>state</c> and <c>enabled</c> are decoded
+	when <c>decode__Window_exclusive</c> is called.</p>
       <p></p>
       <image file="exclusive_Win_But.gif">
-        <icaption>Figure symbolizes the bytes of a Window:status message. The components buttonList and actions are excluded from decode. Only state and enabled are decoded when decode__Window_exclusive is called. </icaption>
+        <icaption>Bytes of a Window:status Message</icaption>
       </image>
       <p></p>
-      <p>Compiling GUI.asn including the configuration file is done like:</p>
+      <p>Compiling <c>GUI.asn</c> including the configuration file is done
+        as follows:</p>
       <pre>
 unix> erlc -bber_bin +optimize +asn1config GUI.asn
 
-erlang> asn1ct:compile('GUI',[ber_bin,optimize,asn1config]).      </pre>
-      <p>The module can be used like:</p>
+erlang> asn1ct:compile('GUI',[ber_bin,optimize,asn1config]).</pre>
+      <p>The module can be used as follows:</p>
       <pre>
-
 1> Button_Msg = {'Button',123,true}.
 {'Button',123,true}
 2> {ok,Button_Bytes} = 'GUI':encode('Button',Button_Msg).
@@ -289,35 +306,39 @@ BoolOpt,{Type_Key_Choice,Val_Choice}}}}=
 11> 'GUI':decode_part(Type_Key_SeqOf,hd(Val_SEQOF)).
 {ok,{'Button',3,true}}
 12> 'GUI':decode_part(Type_Key_Choice,Val_Choice).  
-{ok,{possibleActions,[{'Action',16,{'Button',17,true}}]}}
-      </pre>
+{ok,{possibleActions,[{'Action',16,{'Button',17,true}}]}}</pre>
     </section>
   </section>
 
   <section>
     <title>Selective Decode</title>
-    <p>This specialized decode decodes one single subtype of a
-      constructed value. It is the fastest method to extract one sub
-      value. The typical use of this decode is when one want to
-      inspect, for instance a version number,to be able to decide what
+    <p>This specialized decode decodes a subtype of a
+      constructed value and is the fastest method to extract a
+      subvalue. This decode is typically used when you want to
+      inspect, for example, a version number, to be able to decide what
       to do with the entire value. The result is returned as
       <c>{ok,Value}</c> or <c>{error,Reason}</c>.
       </p>
 
     <section>
-      <title>How To Make It Work</title>
-      <p>The following steps are necessary:
+      <title>Procedure</title>
+      <p>To perform a selective decode:
         </p>
       <list type="bulleted">
-        <item>Write instructions in the configuration
-         file. Including the name of a user function, the name of the ASN.1
-         specification and a notation that tells which part of the type
-         will be decoded. </item>
-        <item>Compile with the additional option
-        <c>asn1config</c>. The compiler searches for a configuration file
-         with the same name as the ASN.1 spec but with the extension
-         .asn1config. In the same file you can provide configuration specs
-         for exclusive decode as well. The generated Erlang module has the
+        <item><p><em>Step 1:</em> Include the following instructions in
+	 the configuration file:</p>
+         <list type="bulleted">
+           <item>The name of the user function</item>
+           <item>The name of the ASN.1 specification</item>
+           <item>A notation that tells which part of the type to be
+           decoded</item>
+	 </list></item>
+        <item><em>Step 2:</em> Compile with the additional option
+         <c>asn1config</c>. The compiler searches for a configuration file
+         with the same name as the ASN.1 specification, but with extension
+         <c>.asn1config</c>. In the same file you can also provide
+	 configuration specifications for exclusive decode.
+         The generated Erlang module has the
          usual functionality for encode/decode preserved and the
          specialized decode functionality added. </item>
       </list>
@@ -326,21 +347,20 @@ BoolOpt,{Type_Key_Choice,Val_Choice}}}}=
     <section>
       <title>User Interface</title>
       <p>The only new user interface function is the one provided by the
-        user in the configuration file. You can invoke that function by
+        user in the configuration file. The function is started by
         the <c>ModuleName:FunctionName</c> notation.
         </p>
-      <p>So, if you have the following spec
+      <p>For example, if the configuration file includes the specification
         <c>{selective_decode,{'ModuleName',[{selected_decode_Window,TypeList}]}}</c>
-        in the con-fig file, you do the selective decode by
+        do the selective decode by
         <c>{ok,Result}='ModuleName':selected_decode_Window(EncodedBinary).</c></p>
     </section>
 
     <section>
       <marker id="Selective Instruction"></marker>
       <title>Writing a Selective Decode Instruction</title>
-      <p>It is possible to describe one or many selective decode
-        functions in a configuration file, you have to use the following
-        notation:</p>
+      <p>One or more selective decode functions can be described in a
+        configuration file. Use the following notation:</p>
       <pre>
 Selective_Decode_Instruction = {selective_decode,{Module_Name,Decode_Instructions}}.
 
@@ -358,37 +378,43 @@ Element_List = Name|List_Selector
 
 Name = atom()
 
-List_Selector = [integer()]      </pre>
-      <p>Observe that the instruction must be a valid Erlang term ended
-        by a dot.
-        </p>
-      <p>The <c>Module_Name</c> is the same as the name of the ASN.1
-        spec, but without the extension. A <c>Decode_Instruction</c> is
-        a tuple with your chosen function name and the components from
-        the top type that leads to the single type you want to
-        decode. Notice that you have to choose a name of your function
-        that will not be the same as any of the generated functions. The
-        first element of the <c>Type_List</c> is the top type of the
-        encoded message. In the <c>Element_List</c> it is followed by
-        each of the component names that leads to selected type. Each of
-        the names in the <c>Element_List</c> must be constructed types
-        except the last name, which can be any type.
+List_Selector = [integer()]</pre>
+      <p>The instruction must be a valid Erlang term ended by a dot.
         </p>
-      <p>The List_Selector makes it possible to choose one of the
-        encoded components in a SEQUENCE OF/ SET OF. It is also possible
-        to go further in that component and pick a sub type of that to
-        decode. So in the <c>Type_List</c>: <c>['Window',status,buttonList,[1],number]</c> the
-        component <c>buttonList</c> has to be a SEQUENCE OF or SET OF type. In
-        this example component <c>number</c> of the first of the encoded
-        elements in the SEQUENCE OF <c>buttonList</c> is selected. This apply on
-        the ASN.1 spec <seealso marker="#Asn1spec">above</seealso>.
+      <list type="bulleted">
+        <item><c>Module_Name</c> is the same as the name of the ASN.1
+        specification, but without the extension.</item>
+      <item><c>Decode_Instruction</c> is a tuple with your chosen
+        function name and the components from the top type that leads
+        to the single type you want to decode. Ensure to choose a name
+        of your function that is not the same as any of the generated
+        functions.</item>
+      <item> The first element of <c>Type_List</c> is the top type of the
+        encoded message. In <c>Element_List</c>, it is followed by
+        each of the component names that leads to selected type.</item>
+      <item>Each name in <c>Element_List</c> must be a constructed type
+        except the last name, which can be any type.</item>
+      <item><c>List_Selector</c> makes it possible to choose one of the
+        encoded components in a a <c>SEQUENCE OF</c> or a <c>SET OF</c>.
+        It is also possible to go further in that component and pick a
+        subtype of that to decode. So, in the <c>Type_List</c>:
+        <c>['Window',status,buttonList,[1],number]</c>, component
+        <c>buttonList</c> must be of type <c>SEQUENCE OF</c> or
+        <c>SET OF</c>.</item>
+      </list>
+      <p>In the example, component <c>number</c> of the first of the encoded
+        elements in the <c>SEQUENCE OF</c> <c>buttonList</c> is selected.
+        This applies on the ASN.1 specification in Section
+        <seealso marker="#Asn1spec">Writing an Exclusive Decode
+        Instruction</seealso>.
         </p>
     </section>
 
     <section>
       <title>Another Example</title>
-      <p>In this example we use the same ASN.1 spec as <seealso marker="#Asn1spec">above</seealso>. A valid selective decode
-        instruction is:</p>
+      <p>In this example, the same ASN.1 specification as in Section
+        <seealso marker="#Asn1spec">Writing an Exclusive Decode Instruction</seealso>
+         is used. The following is a valid selective decode instruction:</p>
       <pre>
 {selective_decode,
     {'GUI',
@@ -404,16 +430,17 @@ List_Selector = [integer()]      </pre>
       actions,
       possibleActions,
       [1],
-      handle,number]}]}}.
-      </pre>
-      <p>The first <c>Decode_Instruction</c>,
+      handle,number]}]}}.</pre>
+      <p>The first instruction,
         <c>{selected_decode_Window1,['Window',status,buttonList,[1],number]}</c>
-        is commented in the previous section. The instruction
-        <c>{selected_decode_Action,['Action',handle,number]}</c> picks
-        the component <c>number</c> in the <c>handle</c> component of the type
-        <c>Action</c>. If we have the value <c>ValAction = {'Action',17,{'Button',4711,false}}</c> the internal value 4711
-        should be picked by <c>selected_decode_Action</c>. In an Erlang
-        terminal it looks like:</p>
+        is described in the previous section.</p>
+      <p> The second instruction,
+        <c>{selected_decode_Action,['Action',handle,number]}</c>, takes
+        component <c>number</c> in the <c>handle</c> component of type
+        <c>Action</c>. If the value is
+        <c>ValAction = {'Action',17,{'Button',4711,false}}</c>, the internal
+        value 4711 is to be picked by <c>selected_decode_Action</c>. In an
+        Erlang terminal it looks as follows:</p>
       <pre>
 ValAction = {'Action',17,{'Button',4711,false}}.
 {'Action',17,{'Button',4711,false}}
@@ -423,44 +450,41 @@ ValAction = {'Action',17,{'Button',4711,false}}.
 &lt;&lt;48,18,2,1,17,160,13,172,11,171,9,48,7,128,2,18,103,129,1,0&gt;&gt;
 9> 'GUI':selected_decode_Action(BinBytes).
 {ok,4711}
-10>       </pre>
+10></pre>
       <p>The third instruction,
         <c>['Window',status,actions,possibleActions,[1],handle,number]</c>,
-        which is a little more complicated,</p>
+        works as follows:</p>
       <list type="bulleted">
-        <item>starts with type <em>Window</em>. </item>
-        <item>Picks component <em>status</em> of <c>Window</c> that is
-         of type <c>Status</c>.</item>
-        <item>Then takes component <em>actions</em> of type
+        <item><em>Step 1:</em> Starts with type <c>Window</c>.</item>
+        <item><em>Step 2:</em> Takes component <c>status</c> of <c>Window</c>
+         that is of type <c>Status</c>.</item>
+        <item><em>Step 3:</em> Takes <em>actions</em> of type
         <c>Status</c>.</item>
-        <item>Then <em>possibleActions</em> of the internal defined
-         CHOICE type.</item>
-        <item>Thereafter it goes into the first component of the
-         SEQUENCE OF by <em>[1]</em>. That component is of type
-        <c>Action</c>.</item>
-        <item>The instruction next picks component
-        <em>handle</em>.</item>
-        <item>And finally component <em>number</em> of the type
+        <item><em>Step 4:</em> Takes <c>possibleActions</c> of the internally
+         defined <c>CHOICE</c> type.</item>
+        <item><em>Step 5:</em> Goes into the first component of
+         <c>SEQUENCE OF</c> by <c>[1]</c>. That component is of type
+         <c>Action</c>.</item>
+        <item><em>Step 6:</em> Takes component <c>handle</c>.</item>
+        <item><em>Step 7:</em> Takes component <c>number</c> of type
         <c>Button</c>.</item>
       </list>
-      <p>The following figures shows which components are in the
-        TypeList
-        <c>['Window',status,actions,possibleActions,[1],handle,number]</c>. And
-        which part of a message that will be decoded by
-        selected_decode_Window2.
-        </p>
+      <p>The following figure shows which components are in <c>TypeList</c>
+        <c>['Window',status,actions,possibleActions,[1],handle,number]</c>:</p>
       <p></p>
       <image file="selective_TypeList.gif">
-        <icaption>The elements specified in the config file for selective decode of a sub-value in a Window message</icaption>
+        <icaption>Elements Specified in Configuration File for Selective Decode of a Subvalue in a Window Message</icaption>
       </image>
+      <p>In the following figure, only the marked element is decoded by
+        <c>selected_decode_Window2</c>:</p>
       <p></p>
       <image file="selective_Window2.gif">
-        <icaption>Figure symbolizes the bytes of a Window:status message. Only the marked element is decoded when selected_decode_Window2 is called. </icaption>
+        <icaption>Bytes of a Window:status Message</icaption>
       </image>
-      <p>With the following example you can examine that both
+      <p>With the following example, you can examine that both
         <c>selected_decode_Window2</c> and
-        <c>selected_decode_Window1</c> decodes the intended sub-value
-        of the value <c>Val</c></p>
+        <c>selected_decode_Window1</c> decodes the intended subvalue
+        of value <c>Val</c>:</p>
       <pre>
 1> Val = {'Window',{status,{'Status',12,
                     [{'Button',13,true},
@@ -478,8 +502,8 @@ ValAction = {'Action',17,{'Button',4711,false}}.
 4> 'GUI':selected_decode_Window1(Bin).
 {ok,13}
 5> 'GUI':selected_decode_Window2(Bin).
-{ok,18}      </pre>
-      <p>Observe that the value feed into the selective decode
+{ok,18}</pre>
+      <p>Notice that the value fed into the selective decode
         functions must be a binary.
         </p>
     </section>
@@ -489,19 +513,19 @@ ValAction = {'Action',17,{'Button',4711,false}}.
     <title>Performance</title>
     <p>To give an indication on the possible performance gain using
       the specialized decodes, some measures have been performed. The
-      relative figures in the outcome between selective, exclusive and
-      complete decode (the normal case) depends on the structure of
-      the type, the size of the message and on what level the
+      relative figures in the outcome between selective, exclusive, and
+      complete decode (the normal case) depend on the structure of
+      the type, the size of the message, and on what level the
       selective and exclusive decodes are specified.
       </p>
 
     <section>
-      <title>ASN.1 Specifications, Messages and Configuration</title>
-      <p>The specs <seealso marker="#Asn1spec">GUI</seealso> and
+      <title>ASN.1 Specifications, Messages, and Configuration</title>
+      <p>The specifications <seealso marker="#Asn1spec">GUI</seealso> and
         <url href="http://www.itu.int/ITU-T/asn1/database/itu-t/h/h248/2002/MEDIA-GATEWAY-CONTROL.html">MEDIA-GATEWAY-CONTROL</url>
-        was used in the test.
+        were used in the test.
         </p>
-      <p>For the GUI spec the configuration looked like:</p>
+      <p>For the <c>GUI</c> specification the configuration was as follows:</p>
       <pre>
 {selective_decode,
   {'GUI',
@@ -523,9 +547,8 @@ ValAction = {'Action',17,{'Button',4711,false}}.
                 ['Window',
                  [{status,
                      [{buttonList,parts},
-                      {actions,undecoded}]}]]}]}}.
-      </pre>
-      <p>The MEDIA-GATEWAY-CONTROL configuration was:</p>
+                      {actions,undecoded}]}]]}]}}.</pre>
+      <p>The <c>MEDIA-GATEWAY-CONTROL</c> configuration was as follows:</p>
       <pre>
 {exclusive_decode,
   {'MEDIA-GATEWAY-CONTROL',
@@ -538,9 +561,8 @@ ValAction = {'Action',17,{'Button',4711,false}}.
 {selective_decode,
   {'MEDIA-GATEWAY-CONTROL',
     [{decode_MegacoMessage_selective,
-         ['MegacoMessage',mess,version]}]}}.
-      </pre>
-      <p>The corresponding values were:</p>
+         ['MegacoMessage',mess,version]}]}}.</pre>
+      <p>The corresponding values were as follows:</p>
       <pre>
 {'Window',{status,{'Status',12,
               [{'Button',13,true},
@@ -649,177 +671,178 @@ ValAction = {'Action',17,{'Button',4711,false}}.
                 {'StatisticsParameter',[0,11,0,3],[[52,53,49,48,48]]},
                 {'StatisticsParameter',[0,12,0,6],[[48,46,50]]},
                 {'StatisticsParameter',[0,12,0,7],[[50,48]]},
-                {'StatisticsParameter',[0,12,0,8],[[52,48]]}]}]}}}]}]}}}]}}}      
-      </pre>
-      <p>The size of the encoded values was 458 bytes for GUI and 464
-        bytes for MEDIA-GATEWAY-CONTROL.
+                {'StatisticsParameter',[0,12,0,8],[[52,48]]}]}]}}}]}]}}}]}}}</pre>
+      <p>The size of the encoded values was 458 bytes for <c>GUI</c> and 464
+        bytes for <c>MEDIA-GATEWAY-CONTROL</c>.
         </p>
     </section>
 
     <section>
       <title>Results</title>
-      <p>The ASN.1 specs in the test are compiled with the options
-        <c>ber_bin, optimize, driver</c> and <c>asn1config</c>. If the
-        <c>driver</c> option had been omitted there should have been
+      <p>The ASN.1 specifications in the test were compiled with options
+        <c>ber_bin, optimize, driver</c> and <c>asn1config</c>. Omitting
+        option <c>driver</c> gives
         higher values for <c>decode</c> and <c>decode_part</c>. These tests have
-	not been re-run using nifs, but are expected to perform about 5% better
+	not been rerun using NIFs, but are expected to perform about 5% better
 	than the linked-in driver.
         </p>
       <p>The test program runs 10000 decodes on the value, resulting
-        in a printout with the elapsed time in microseconds for the
+        in an output with the elapsed time in microseconds for the
         total number of decodes.
         </p>
       <table>
         <row>
           <cell align="left" valign="top"><em>Function</em></cell>
-          <cell align="left" valign="top"><em>Time</em>(microseconds)</cell>
-          <cell align="left" valign="top"><em>Kind of Decode</em></cell>
-          <cell align="left" valign="top"><em>ASN.1 spec</em></cell>
-          <cell align="left" valign="top"><em>% of time vs. complete decode</em></cell>
+          <cell align="left" valign="top"><em>Time</em> (microseconds)</cell>
+          <cell align="left" valign="top"><em>Decode Type</em></cell>
+          <cell align="left" valign="top"><em>ASN.1 Specification</em></cell>
+          <cell align="left" valign="top"><em>% of Time versus Complete Decode</em></cell>
         </row>
         <row>
           <cell align="left" valign="middle"><c>decode_MegacoMessage_selective/1</c></cell>
           <cell align="left" valign="middle"><c>374045</c></cell>
-          <cell align="left" valign="middle"><c>selective</c></cell>
+          <cell align="left" valign="middle"><c>Selective</c></cell>
           <cell align="left" valign="middle"><c>MEDIA-GATEWAY-CONTROL</c></cell>
           <cell align="left" valign="middle"><em>8.3</em></cell>
         </row>
         <row>
           <cell align="left" valign="middle"><c>decode_MegacoMessage_exclusive/1</c></cell>
           <cell align="left" valign="middle"><c>621107</c></cell>
-          <cell align="left" valign="middle"><c>exclusive</c></cell>
+          <cell align="left" valign="middle"><c>Exclusive</c></cell>
           <cell align="left" valign="middle"><c>MEDIA-GATEWAY-CONTROL</c></cell>
           <cell align="left" valign="middle"><em>13.8</em></cell>
         </row>
         <row>
           <cell align="left" valign="middle"><c>decode/2</c></cell>
           <cell align="left" valign="middle"><c>4507457</c></cell>
-          <cell align="left" valign="middle"><c>complete</c></cell>
+          <cell align="left" valign="middle"><c>Complete</c></cell>
           <cell align="left" valign="middle"><c>MEDIA-GATEWAY-CONTROL</c></cell>
           <cell align="left" valign="middle"><em>100</em></cell>
         </row>
         <row>
           <cell align="left" valign="middle"><c>selected_decode_Window1/1</c></cell>
           <cell align="left" valign="middle"><c>449585</c></cell>
-          <cell align="left" valign="middle"><c>selective</c></cell>
+          <cell align="left" valign="middle"><c>Selective</c></cell>
           <cell align="left" valign="middle"><c>GUI</c></cell>
           <cell align="left" valign="middle"><em>7.6</em></cell>
         </row>
         <row>
           <cell align="left" valign="middle"><c>selected_decode_Window2/1</c></cell>
           <cell align="left" valign="middle"><c>890666</c></cell>
-          <cell align="left" valign="middle"><c>selective</c></cell>
+          <cell align="left" valign="middle"><c>Selective</c></cell>
           <cell align="left" valign="middle"><c>GUI</c></cell>
           <cell align="left" valign="middle"><em>15.1</em></cell>
         </row>
         <row>
           <cell align="left" valign="middle"><c>decode_Window_status_exclusive/1</c></cell>
           <cell align="left" valign="middle"><c>1251878</c></cell>
-          <cell align="left" valign="middle"><c>exclusive</c></cell>
+          <cell align="left" valign="middle"><c>Exclusive</c></cell>
           <cell align="left" valign="middle"><c>GUI</c></cell>
           <cell align="left" valign="middle"><em>21.3</em></cell>
         </row>
         <row>
           <cell align="left" valign="middle"><c>decode/2</c></cell>
           <cell align="left" valign="middle"><c>5889197</c></cell>
-          <cell align="left" valign="middle"><c>complete</c></cell>
+          <cell align="left" valign="middle"><c>Complete</c></cell>
           <cell align="left" valign="middle"><c>GUI</c></cell>
           <cell align="left" valign="middle"><em>100</em></cell>
         </row>
-        <tcaption>Results of complete, exclusive and selective decode</tcaption>
+        <tcaption>Results of Complete, Exclusive, and Selective Decode</tcaption>
       </table>
-      <p>Another interesting question is what the relation is between
+      <p>It is also of interest to know the relation is between
         a complete decode, an exclusive decode followed by
-        <c>decode_part</c> of the excluded parts and a selective decode
-        followed by a complete decode. Some situations may be compared to
-        this simulation, e.g. inspect a sub-value and later on look at
+        <c>decode_part</c> of the excluded parts, and a selective decode
+        followed by a complete decode. Some situations can be compared to
+        this simulation, for example, inspect a subvalue and later inspect
         the entire value. The following table shows figures from this
-        test. The number of loops and time unit is the same as in the
+        test. The number of loops and the time unit are the same as in the
         previous test.
         </p>
       <table>
         <row>
           <cell align="left" valign="top"><em>Actions</em></cell>
           <cell align="left" valign="top"><em>Function</em>&nbsp;&nbsp;&nbsp;&nbsp;</cell>
-          <cell align="left" valign="top"><em>Time</em>(microseconds)</cell>
-          <cell align="left" valign="top"><em>ASN.1 spec</em></cell>
-          <cell align="left" valign="top"><em>% of time vs. complete decode</em></cell>
+          <cell align="left" valign="top"><em>Time</em> (microseconds)</cell>
+          <cell align="left" valign="top"><em>ASN.1 Specification</em></cell>
+          <cell align="left" valign="top"><em>% of Time vs. Complete Decode</em></cell>
         </row>
         <row>
-          <cell align="left" valign="middle"><c>complete</c></cell>
+          <cell align="left" valign="middle"><c>Complete</c></cell>
           <cell align="left" valign="middle"><c>decode/2</c></cell>
           <cell align="left" valign="middle"><c>4507457</c></cell>
           <cell align="left" valign="middle"><c>MEDIA-GATEWAY-CONTROL</c></cell>
           <cell align="left" valign="middle"><em>100</em></cell>
         </row>
         <row>
-          <cell align="left" valign="middle"><c>selective and complete</c></cell>
+          <cell align="left" valign="middle"><c>Selective and Complete</c></cell>
           <cell align="left" valign="middle"><c>decode_&shy;MegacoMessage_&shy;selective/1</c></cell>
           <cell align="left" valign="middle"><c>4881502</c></cell>
           <cell align="left" valign="middle"><c>MEDIA-GATEWAY-CONTROL</c></cell>
           <cell align="left" valign="middle"><em>108.3</em></cell>
         </row>
         <row>
-          <cell align="left" valign="middle"><c>exclusive and decode_part</c></cell>
+          <cell align="left" valign="middle"><c>Exclusive and decode_part</c></cell>
           <cell align="left" valign="middle"><c>decode_&shy;MegacoMessage_&shy;exclusive/1</c></cell>
           <cell align="left" valign="middle"><c>5481034</c></cell>
           <cell align="left" valign="middle"><c>MEDIA-GATEWAY-CONTROL</c></cell>
           <cell align="left" valign="middle"><em>112.3</em></cell>
         </row>
         <row>
-          <cell align="left" valign="middle"><c>complete</c></cell>
+          <cell align="left" valign="middle"><c>Complete</c></cell>
           <cell align="left" valign="middle"><c>decode/2</c></cell>
           <cell align="left" valign="middle"><c>5889197</c></cell>
           <cell align="left" valign="middle"><c>GUI</c></cell>
           <cell align="left" valign="middle"><em>100</em></cell>
         </row>
         <row>
-          <cell align="left" valign="middle"><c>selective and complete</c></cell>
+          <cell align="left" valign="middle"><c>Selective and Complete</c></cell>
           <cell align="left" valign="middle"><c>selected_&shy;decode_&shy;Window1/1</c></cell>
           <cell align="left" valign="middle"><c>6337636</c></cell>
           <cell align="left" valign="middle"><c>GUI</c></cell>
           <cell align="left" valign="middle"><em>107.6</em></cell>
         </row>
         <row>
-          <cell align="left" valign="middle"><c>selective and complete</c></cell>
+          <cell align="left" valign="middle"><c>Selective and Complete</c></cell>
           <cell align="left" valign="middle"><c>selected_&shy;decode_&shy;Window2/1</c></cell>
           <cell align="left" valign="middle"><c>6795319</c></cell>
           <cell align="left" valign="middle"><c>GUI</c></cell>
           <cell align="left" valign="middle"><em>115.4</em></cell>
         </row>
         <row>
-          <cell align="left" valign="middle"><c>exclusive and decode_part</c></cell>
+          <cell align="left" valign="middle"><c>Exclusive and decode_part</c></cell>
           <cell align="left" valign="middle"><c>decode_&shy;Window_&shy;status_&shy;exclusive/1</c></cell>
           <cell align="left" valign="middle"><c>6249200</c></cell>
           <cell align="left" valign="middle"><c>GUI</c></cell>
           <cell align="left" valign="middle"><em>106.1</em></cell>
         </row>
-        <tcaption>Results of complete, exclusive + decode_part and selective + complete decodes</tcaption>
+        <tcaption>Results of Complete, Exclusive + decode_part, and Selective + complete decodes</tcaption>
       </table>
       <p>Other ASN.1 types and values can differ much from these
-        figures. Therefore it is important that you, in every case where
+        figures. It is therefore important that you, in every case where
         you intend to use either of these decodes, perform some tests
-        that shows if you will benefit your purpose.
+        that show if you will benefit your purpose.
         </p>
     </section>
 
     <section>
-      <title>Comments</title>
-      <p>Generally speaking the gain of selective and exclusive decode
-        in advance of complete decode is greater the bigger value and the
-        less deep in the structure you have to decode. One should also
-        prefer selective decode instead of exclusive decode if you are
-        interested in just one single sub-value.</p>
-      <p>Another observation is that the exclusive decode followed by
-        decode_part decodes is very attractive if the parts will be sent
-        to different servers for decoding or if one in some cases not is
-        interested in all parts.</p>
-      <p>The fastest selective decode are when the decoded type is a
+      <title>Final Remarks</title>
+      <list type="bulleted">
+      <item>The gain of using selective and exclusive decode instead of a
+        complete decode is greater the bigger the value and the
+        less deep in the structure you have to decode.</item>
+      <item>Use selective decode instead of exclusive decode if you are
+        interested in only a single subvalue.</item>
+      <item>Exclusive decode followed by
+        <c>decode_part</c> decodes is attractive if the parts are sent
+        to different servers for decoding, or if you in some cases are not
+        interested in all parts.</item>
+      <item>The fastest selective decode is when the decoded type is a
         primitive type and not so deep in the structure of the top
-        type. The <c>selected_decode_Window2</c> decodes a big constructed
-        value, which explains why this operation is relatively slow.</p>
-      <p>It may vary from case to case which combination of
-        selective/complete decode or exclusive/part decode is the fastest.</p>
+        type. <c>selected_decode_Window2</c> decodes a high constructed
+        value, which explains why this operation is relatively slow.</item>
+      <item>It can vary from case to case which combination of
+        selective/complete decode or exclusive/part decode is the fastest.</item>
+      </list>
     </section>
   </section>
 </chapter>