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>The <SPAN
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>The <SPAN
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>eCos</SPAN
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>eCos</SPAN
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> Component Writer's Guide</TH
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> Component Writer's Guide</TH
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>Prev</A
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VALIGN="bottom"
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>Chapter 3. The CDL Language</TD
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>Chapter 3. The CDL Language</TD
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><TD
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><DIV
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CLASS="SECT1"
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><H1
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><H1
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CLASS="SECT1"
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CLASS="SECT1"
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><A
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><A
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NAME="LANGUAGE.TCL">An Introduction to Tcl</H1
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NAME="LANGUAGE.TCL">An Introduction to Tcl</H1
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><P
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><P
|
>All <SPAN
|
>All <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> scripts are implemented as <SPAN
|
> scripts are implemented as <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> scripts, and are read in by
|
> scripts, and are read in by
|
running the data through a standard <SPAN
|
running the data through a standard <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> interpreter, extended with a
|
> interpreter, extended with a
|
small number of additional commands such as
|
small number of additional commands such as
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>cdl_option</TT
|
>cdl_option</TT
|
> and <TT
|
> and <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>cdl_component</TT
|
>cdl_component</TT
|
>.
|
>.
|
Often it is not necessary to know the full details of <SPAN
|
Often it is not necessary to know the full details of <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> syntax.
|
> syntax.
|
Instead it is possible to copy an existing script, perform some copy
|
Instead it is possible to copy an existing script, perform some copy
|
and paste operations, and make appropriate changes to names and to
|
and paste operations, and make appropriate changes to names and to
|
various properties. However there are also cases where an
|
various properties. However there are also cases where an
|
understanding of <SPAN
|
understanding of <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> syntax is very desirable, for example:</P
|
> syntax is very desirable, for example:</P
|
><TABLE
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><TABLE
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BORDER="5"
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BORDER="5"
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BGCOLOR="#E0E0F0"
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BGCOLOR="#E0E0F0"
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WIDTH="70%"
|
WIDTH="70%"
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><TR
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><TR
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><TD
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><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>cdl_option CYGDAT_UITRON_MEMPOOLFIXED_EXTERNS {
|
>cdl_option CYGDAT_UITRON_MEMPOOLFIXED_EXTERNS {
|
display "Externs for initialization"
|
display "Externs for initialization"
|
flavor data
|
flavor data
|
default_value {"static char fpool1[ 2000 ], \\\n\
|
default_value {"static char fpool1[ 2000 ], \\\n\
|
fpool2[ 2000 ], \\\n\
|
fpool2[ 2000 ], \\\n\
|
fpool3[ 2000 ];"}
|
fpool3[ 2000 ];"}
|
…
|
…
|
}</PRE
|
}</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>This causes the <TT
|
>This causes the <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>cdl_option</TT
|
>cdl_option</TT
|
> command to be executed, which in turn
|
> command to be executed, which in turn
|
evaluates its body in a recursive invocation of the <SPAN
|
evaluates its body in a recursive invocation of the <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> interpreter.
|
> interpreter.
|
When the <SPAN
|
When the <SPAN
|
CLASS="PROPERTY"
|
CLASS="PROPERTY"
|
>default_value</SPAN
|
>default_value</SPAN
|
> property is encountered the braces around the
|
> property is encountered the braces around the
|
value part are processed by the interpreter, stopping it from doing
|
value part are processed by the interpreter, stopping it from doing
|
further processing of the braced contents (except for backslash
|
further processing of the braced contents (except for backslash
|
processing at the end of a line, that is special). In particular it
|
processing at the end of a line, that is special). In particular it
|
prevents command substitution for
|
prevents command substitution for
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>[ 2000 ]</TT
|
>[ 2000 ]</TT
|
>. A single argument will be
|
>. A single argument will be
|
passed to the <SPAN
|
passed to the <SPAN
|
CLASS="PROPERTY"
|
CLASS="PROPERTY"
|
>default_value</SPAN
|
>default_value</SPAN
|
> command which expects a <SPAN
|
> command which expects a <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
>
|
>
|
expression, so the expression parsing code is passed the following:</P
|
expression, so the expression parsing code is passed the following:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="SCREEN"
|
CLASS="SCREEN"
|
>"static char fpool1[ 2000 ], \\\n fpool2[ 2000 ], \\\n fpool3[ 2000 ];"</PRE
|
>"static char fpool1[ 2000 ], \\\n fpool2[ 2000 ], \\\n fpool3[ 2000 ];"</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>The <SPAN
|
>The <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> expression parsing code will treat this as a simple string
|
> expression parsing code will treat this as a simple string
|
constant, as opposed to a more complicated expression involving other
|
constant, as opposed to a more complicated expression involving other
|
options and various operators. The string parsing code will perform
|
options and various operators. The string parsing code will perform
|
the usual backslash substitutions so the actual default value will be:</P
|
the usual backslash substitutions so the actual default value will be:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="SCREEN"
|
CLASS="SCREEN"
|
>static char fpool1[ 2000 ], \
|
>static char fpool1[ 2000 ], \
|
fpool2[ 2000 ], \
|
fpool2[ 2000 ], \
|
fpool3[ 2000 ];</PRE
|
fpool3[ 2000 ];</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>If the user does not modify the option's value then the following
|
>If the user does not modify the option's value then the following
|
will be generated in the appropriate configuration header file:</P
|
will be generated in the appropriate configuration header file:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>#define CYGDAT_UITRON_MEMPOOLFIXED_EXTERNS static char fpool1[ 2000 ], \
|
>#define CYGDAT_UITRON_MEMPOOLFIXED_EXTERNS static char fpool1[ 2000 ], \
|
fpool2[ 2000 ], \
|
fpool2[ 2000 ], \
|
fpool3[ 2000 ];</PRE
|
fpool3[ 2000 ];</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>Getting this desired result usually requires an understanding of both
|
>Getting this desired result usually requires an understanding of both
|
<SPAN
|
<SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> syntax and <SPAN
|
> syntax and <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> expression syntax. Sometimes it is possible to
|
> expression syntax. Sometimes it is possible to
|
substitute a certain amount of trial and error instead, but this may
|
substitute a certain amount of trial and error instead, but this may
|
prove frustrating. It is also worth pointing out that many <SPAN
|
prove frustrating. It is also worth pointing out that many <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
>
|
>
|
scripts do not involve this level of complexity. On the other hand,
|
scripts do not involve this level of complexity. On the other hand,
|
some of the more advanced features of the <SPAN
|
some of the more advanced features of the <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> language involve
|
> language involve
|
fragments of <SPAN
|
fragments of <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> code, for example the <SPAN
|
> code, for example the <SPAN
|
CLASS="PROPERTY"
|
CLASS="PROPERTY"
|
>define_proc</SPAN
|
>define_proc</SPAN
|
> property. To
|
> property. To
|
use these component writers will need to know about the full <SPAN
|
use these component writers will need to know about the full <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
>
|
>
|
language as well as the syntax.</P
|
language as well as the syntax.</P
|
><P
|
><P
|
>Although the current example may seem to suggest that <SPAN
|
>Although the current example may seem to suggest that <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> is rather
|
> is rather
|
complicated, it is actually a very simple yet powerful scripting
|
complicated, it is actually a very simple yet powerful scripting
|
language: the syntax is defined by just eleven rules. On occasion this
|
language: the syntax is defined by just eleven rules. On occasion this
|
simplicity means that Tcl's behavior is subtly different from other
|
simplicity means that Tcl's behavior is subtly different from other
|
languages, which can confuse newcomers.</P
|
languages, which can confuse newcomers.</P
|
><P
|
><P
|
>When the Tcl interpreter is passed some data such as
|
>When the Tcl interpreter is passed some data such as
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>puts Hello</TT
|
>puts Hello</TT
|
>, it splits this data into a command
|
>, it splits this data into a command
|
and its arguments. The command will be terminated by a newline or by a
|
and its arguments. The command will be terminated by a newline or by a
|
semicolon, unless one of the quoting mechanisms is used. The command
|
semicolon, unless one of the quoting mechanisms is used. The command
|
and each of its arguments are separated by white space. So in the
|
and each of its arguments are separated by white space. So in the
|
following example:</P
|
following example:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="SCREEN"
|
CLASS="SCREEN"
|
>puts Hello
|
>puts Hello
|
set x 42</PRE
|
set x 42</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>This will result in two separate commands being executed. The first
|
>This will result in two separate commands being executed. The first
|
command is <TT
|
command is <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>puts</TT
|
>puts</TT
|
> and is passed a single argument,
|
> and is passed a single argument,
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>Hello</TT
|
>Hello</TT
|
>. The second command is <TT
|
>. The second command is <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>set</TT
|
>set</TT
|
>
|
>
|
and is passed two arguments, <TT
|
and is passed two arguments, <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>x</TT
|
>x</TT
|
> and
|
> and
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>42</TT
|
>42</TT
|
>. The intervening newline character serves to
|
>. The intervening newline character serves to
|
terminate the first command, and a semi-colon separator could be used
|
terminate the first command, and a semi-colon separator could be used
|
instead: </P
|
instead: </P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="SCREEN"
|
CLASS="SCREEN"
|
>puts Hello;set x 42</PRE
|
>puts Hello;set x 42</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>Any white space surrounding the semicolon is just ignored because it
|
>Any white space surrounding the semicolon is just ignored because it
|
does not serve to separate arguments.</P
|
does not serve to separate arguments.</P
|
><P
|
><P
|
>Now consider the following:</P
|
>Now consider the following:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="SCREEN"
|
CLASS="SCREEN"
|
>set x Hello world</PRE
|
>set x Hello world</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>This is not valid <SPAN
|
>This is not valid <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
>. It is an attempt to invoke the
|
>. It is an attempt to invoke the
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>set</TT
|
>set</TT
|
> command with three arguments:
|
> command with three arguments:
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>x</TT
|
>x</TT
|
>, <TT
|
>, <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>Hello</TT
|
>Hello</TT
|
>, and
|
>, and
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>world</TT
|
>world</TT
|
>. The <TT
|
>. The <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>set</TT
|
>set</TT
|
> only takes two
|
> only takes two
|
arguments, a variable name and a value, so it is necessary to combine
|
arguments, a variable name and a value, so it is necessary to combine
|
the data into a single argument by quoting:</P
|
the data into a single argument by quoting:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="SCREEN"
|
CLASS="SCREEN"
|
>set x "Hello world"</PRE
|
>set x "Hello world"</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>When the <SPAN
|
>When the <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> interpreter encounters the first quote character it
|
> interpreter encounters the first quote character it
|
treats all subsequent data up to but not including the closing quote
|
treats all subsequent data up to but not including the closing quote
|
as part of the current argument. The quote marks are removed by the
|
as part of the current argument. The quote marks are removed by the
|
interpreter, so the second argument passed to the
|
interpreter, so the second argument passed to the
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>set</TT
|
>set</TT
|
> command is just <TT
|
> command is just <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>Hello world</TT
|
>Hello world</TT
|
>
|
>
|
without the quote characters. This can be significant in the context
|
without the quote characters. This can be significant in the context
|
of <SPAN
|
of <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> scripts. For example:</P
|
> scripts. For example:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>cdl_option CYG_HAL_STARTUP {
|
>cdl_option CYG_HAL_STARTUP {
|
…
|
…
|
default_value "RAM"
|
default_value "RAM"
|
}</PRE
|
}</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>The <SPAN
|
>The <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> interpreter strips off the quote marks so the <SPAN
|
> interpreter strips off the quote marks so the <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
>
|
>
|
expression parsing code sees <TT
|
expression parsing code sees <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>RAM</TT
|
>RAM</TT
|
> instead of
|
> instead of
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>"RAM"</TT
|
>"RAM"</TT
|
>. It will treat this as a reference to
|
>. It will treat this as a reference to
|
some unknown option <TT
|
some unknown option <TT
|
CLASS="VARNAME"
|
CLASS="VARNAME"
|
>RAM</TT
|
>RAM</TT
|
> rather than as a string
|
> rather than as a string
|
constant, and the expression evaluation code will use a value of
|
constant, and the expression evaluation code will use a value of
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>0</TT
|
>0</TT
|
> when it encounters an option that is not
|
> when it encounters an option that is not
|
currently loaded. Therefore the option
|
currently loaded. Therefore the option
|
<TT
|
<TT
|
CLASS="VARNAME"
|
CLASS="VARNAME"
|
>CYG_HAL_STARTUP</TT
|
>CYG_HAL_STARTUP</TT
|
> ends up with a default value of
|
> ends up with a default value of
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>0</TT
|
>0</TT
|
>. Either braces or backslashes should be used to
|
>. Either braces or backslashes should be used to
|
avoid this, for example
|
avoid this, for example
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>default_value { "RAM" }</TT
|
>default_value { "RAM" }</TT
|
>. </P
|
>. </P
|
><DIV
|
><DIV
|
CLASS="NOTE"
|
CLASS="NOTE"
|
><BLOCKQUOTE
|
><BLOCKQUOTE
|
CLASS="NOTE"
|
CLASS="NOTE"
|
><P
|
><P
|
><B
|
><B
|
>Note: </B
|
>Note: </B
|
>There are long-term plans to implement some sort of <SPAN
|
>There are long-term plans to implement some sort of <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> validation
|
> validation
|
utility <SPAN
|
utility <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>cdllint</SPAN
|
>cdllint</SPAN
|
> which
|
> which
|
could catch common errors like this one.</P
|
could catch common errors like this one.</P
|
></BLOCKQUOTE
|
></BLOCKQUOTE
|
></DIV
|
></DIV
|
><P
|
><P
|
>A quoted argument continues until the closing quote character is
|
>A quoted argument continues until the closing quote character is
|
encountered, which means that it can span multiple lines. Newline or
|
encountered, which means that it can span multiple lines. Newline or
|
semicolon characters do not terminate the current command in such
|
semicolon characters do not terminate the current command in such
|
cases. <SPAN
|
cases. <SPAN
|
CLASS="PROPERTY"
|
CLASS="PROPERTY"
|
>description</SPAN
|
>description</SPAN
|
> properties usually make use of this:</P
|
> properties usually make use of this:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>cdl_package CYGPKG_ERROR {
|
>cdl_package CYGPKG_ERROR {
|
description "
|
description "
|
This package contains the common list of error and
|
This package contains the common list of error and
|
status codes. It is held centrally to allow
|
status codes. It is held centrally to allow
|
packages to interchange error codes and status
|
packages to interchange error codes and status
|
codes in a common way, rather than each package
|
codes in a common way, rather than each package
|
having its own conventions for error/status
|
having its own conventions for error/status
|
reporting. The error codes are modelled on the
|
reporting. The error codes are modelled on the
|
POSIX style naming e.g. EINVAL etc. This package
|
POSIX style naming e.g. EINVAL etc. This package
|
also provides the standard strerror() function to
|
also provides the standard strerror() function to
|
convert error codes to textual representation."
|
convert error codes to textual representation."
|
…
|
…
|
}</PRE
|
}</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>The <SPAN
|
>The <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> interpreter supports much the same forms of backslash
|
> interpreter supports much the same forms of backslash
|
substitution as other common programming languages. Some backslash
|
substitution as other common programming languages. Some backslash
|
sequences such as <TT
|
sequences such as <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>\n</TT
|
>\n</TT
|
> will be replaced by the
|
> will be replaced by the
|
appropriate character. The sequence <TT
|
appropriate character. The sequence <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>\\</TT
|
>\\</TT
|
> will be
|
> will be
|
replaced by a single backslash. A backslash at the very end of a line
|
replaced by a single backslash. A backslash at the very end of a line
|
will cause that backslash, the newline character, and any white space
|
will cause that backslash, the newline character, and any white space
|
at the start of the next line to be replaced by a single space. Hence
|
at the start of the next line to be replaced by a single space. Hence
|
the following two Tcl commands are equivalent:</P
|
the following two Tcl commands are equivalent:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>puts "Hello\nworld\n"
|
>puts "Hello\nworld\n"
|
puts \
|
puts \
|
"Hello
|
"Hello
|
world
|
world
|
"</PRE
|
"</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>If a <SPAN
|
>If a <SPAN
|
CLASS="PROPERTY"
|
CLASS="PROPERTY"
|
>description</SPAN
|
>description</SPAN
|
> string needs to contain quote marks or other
|
> string needs to contain quote marks or other
|
special characters then backslash escapes can be used. In addition to
|
special characters then backslash escapes can be used. In addition to
|
quote and backslash characters, the Tcl interpreter treats square
|
quote and backslash characters, the Tcl interpreter treats square
|
brackets, the <TT
|
brackets, the <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>$</TT
|
>$</TT
|
> character, and braces specially.
|
> character, and braces specially.
|
Square brackets are used for command substitution, for example:</P
|
Square brackets are used for command substitution, for example:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="SCREEN"
|
CLASS="SCREEN"
|
>puts "The answer is [expr 6 * 9]"</PRE
|
>puts "The answer is [expr 6 * 9]"</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>When the Tcl interpreter encounters the square brackets it will treat
|
>When the Tcl interpreter encounters the square brackets it will treat
|
the contents as another command that should be executed first, and the
|
the contents as another command that should be executed first, and the
|
result of executing that is used when continuing to process the
|
result of executing that is used when continuing to process the
|
script. In this case the Tcl interpreter will execute the command
|
script. In this case the Tcl interpreter will execute the command
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>expr 6 * 9</TT
|
>expr 6 * 9</TT
|
>, yielding a result of 42
|
>, yielding a result of 42
|
<A
|
<A
|
NAME="AEN1270"
|
NAME="AEN1270"
|
HREF="#FTN.AEN1270"
|
HREF="#FTN.AEN1270"
|
>[1]</A
|
>[1]</A
|
>
|
>
|
and then the
|
and then the
|
Tcl interpreter will execute <TT
|
Tcl interpreter will execute <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>puts "The answer is 42"</TT
|
>puts "The answer is 42"</TT
|
>.
|
>.
|
It should be noted that the interpreter performs only one level
|
It should be noted that the interpreter performs only one level
|
of substitution: if the result of performing command substitution
|
of substitution: if the result of performing command substitution
|
performs further special characters such as square brackets then these
|
performs further special characters such as square brackets then these
|
will not be treated specially.</P
|
will not be treated specially.</P
|
><P
|
><P
|
>Command substitution will not prove useful for many <SPAN
|
>Command substitution will not prove useful for many <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> scripts,
|
> scripts,
|
except for e.g. a <SPAN
|
except for e.g. a <SPAN
|
CLASS="PROPERTY"
|
CLASS="PROPERTY"
|
>define_proc</SPAN
|
>define_proc</SPAN
|
> property which involves a fragment of
|
> property which involves a fragment of
|
<SPAN
|
<SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> code. Potentially there are some interesting uses, for example
|
> code. Potentially there are some interesting uses, for example
|
to internationalize <SPAN
|
to internationalize <SPAN
|
CLASS="PROPERTY"
|
CLASS="PROPERTY"
|
>display</SPAN
|
>display</SPAN
|
> strings. However care does have to be
|
> strings. However care does have to be
|
taken to avoid unexpected command substitution, for example if an
|
taken to avoid unexpected command substitution, for example if an
|
option description involves square brackets then typically these would
|
option description involves square brackets then typically these would
|
require backslash-escapes.</P
|
require backslash-escapes.</P
|
><P
|
><P
|
>The <TT
|
>The <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>$</TT
|
>$</TT
|
> character is used in Tcl scripts to perform
|
> character is used in Tcl scripts to perform
|
variable substitution:</P
|
variable substitution:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>set x [expr 6 * 9]
|
>set x [expr 6 * 9]
|
puts "The answer is $x"</PRE
|
puts "The answer is $x"</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>Variable substitution, like command substitution, is unlikely to
|
>Variable substitution, like command substitution, is unlikely to
|
prove useful for many <SPAN
|
prove useful for many <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> scripts except in the context of
|
> scripts except in the context of
|
<SPAN
|
<SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> fragments. If it is necessary to have a <TT
|
> fragments. If it is necessary to have a <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>$</TT
|
>$</TT
|
>
|
>
|
character then a backslash escape may have to be used.</P
|
character then a backslash escape may have to be used.</P
|
><P
|
><P
|
>Braces are used to collect a sequence of characters into a single
|
>Braces are used to collect a sequence of characters into a single
|
argument, just like quotes. The difference is that variable, command
|
argument, just like quotes. The difference is that variable, command
|
and backslash substitution do not occur inside braces (with the
|
and backslash substitution do not occur inside braces (with the
|
sole exception of backslash substitution at the end of a line).
|
sole exception of backslash substitution at the end of a line).
|
Therefore given a line in a <SPAN
|
Therefore given a line in a <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> script such as:</P
|
> script such as:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>default_value {"RAM"}</PRE
|
>default_value {"RAM"}</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>The braces are stripped off by the <SPAN
|
>The braces are stripped off by the <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> interpreter, leaving
|
> interpreter, leaving
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>"RAM"</TT
|
>"RAM"</TT
|
> which will be handled as a string constant by
|
> which will be handled as a string constant by
|
the expression parsing code. The same effect could be achieved using
|
the expression parsing code. The same effect could be achieved using
|
one of the following:</P
|
one of the following:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>default_value \"RAM\"
|
>default_value \"RAM\"
|
default_value "\"RAM\""</PRE
|
default_value "\"RAM\""</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>Generally the use of braces is less confusing. At this stage it is
|
>Generally the use of braces is less confusing. At this stage it is
|
worth noting that the basic format of <SPAN
|
worth noting that the basic format of <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> data makes use of
|
> data makes use of
|
braces:</P
|
braces:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>cdl_option <name> {
|
>cdl_option <name> {
|
…
|
…
|
};</PRE
|
};</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>The <TT
|
>The <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>cdl_option</TT
|
>cdl_option</TT
|
> command is passed two arguments, a name and a body,
|
> command is passed two arguments, a name and a body,
|
where the body consists of everything inside the braces but not the
|
where the body consists of everything inside the braces but not the
|
braces themselves. This body can then be executed in a recursive
|
braces themselves. This body can then be executed in a recursive
|
invocation of the <SPAN
|
invocation of the <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
> interpreter. If a <SPAN
|
> interpreter. If a <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>CDL</SPAN
|
>CDL</SPAN
|
> script contains
|
> script contains
|
mismatched braces then the interpreter is likely to get rather
|
mismatched braces then the interpreter is likely to get rather
|
confused and the resulting diagnostics may be difficult to understand. </P
|
confused and the resulting diagnostics may be difficult to understand. </P
|
><P
|
><P
|
>Comments in Tcl scripts are introduced by a hash character
|
>Comments in Tcl scripts are introduced by a hash character
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>#</TT
|
>#</TT
|
>. However, a hash character only introduces a
|
>. However, a hash character only introduces a
|
comment if it occurs where a command is expected. Consider the
|
comment if it occurs where a command is expected. Consider the
|
following:</P
|
following:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
># This is a comment
|
># This is a comment
|
puts "Hello" # world</PRE
|
puts "Hello" # world</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>The first line is a valid comment, since the hash character occurs
|
>The first line is a valid comment, since the hash character occurs
|
right at the start where a command name is expected. The second line
|
right at the start where a command name is expected. The second line
|
does not contain a comment. Instead it is an attempt to invoke the
|
does not contain a comment. Instead it is an attempt to invoke the
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>puts</TT
|
>puts</TT
|
> command with three arguments:
|
> command with three arguments:
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>Hello</TT
|
>Hello</TT
|
>, <TT
|
>, <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>#</TT
|
>#</TT
|
> and
|
> and
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>world</TT
|
>world</TT
|
>. These are not valid arguments for the
|
>. These are not valid arguments for the
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>puts</TT
|
>puts</TT
|
> command so an error will be raised.
|
> command so an error will be raised.
|
If the second line was rewritten as:</P
|
If the second line was rewritten as:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>puts "Hello"; # world</PRE
|
>puts "Hello"; # world</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>then this is a valid Tcl script. The semicolon identifies the end of
|
>then this is a valid Tcl script. The semicolon identifies the end of
|
the current command, so the hash character occurs at a point where the
|
the current command, so the hash character occurs at a point where the
|
next command would start and hence it is interpreted as the start of a
|
next command would start and hence it is interpreted as the start of a
|
comment.</P
|
comment.</P
|
><P
|
><P
|
>This handling of comments can lead to subtle behavior. Consider the
|
>This handling of comments can lead to subtle behavior. Consider the
|
following:</P
|
following:</P
|
><TABLE
|
><TABLE
|
BORDER="5"
|
BORDER="5"
|
BGCOLOR="#E0E0F0"
|
BGCOLOR="#E0E0F0"
|
WIDTH="70%"
|
WIDTH="70%"
|
><TR
|
><TR
|
><TD
|
><TD
|
><PRE
|
><PRE
|
CLASS="PROGRAMLISTING"
|
CLASS="PROGRAMLISTING"
|
>cdl_option WHATEVER {
|
>cdl_option WHATEVER {
|
# This is a comment }
|
# This is a comment }
|
default_value 0
|
default_value 0
|
…
|
…
|
}</PRE
|
}</PRE
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><P
|
><P
|
>Consider the way the Tcl interpreter processes this. The command name
|
>Consider the way the Tcl interpreter processes this. The command name
|
and the first argument do not pose any special difficulties. The
|
and the first argument do not pose any special difficulties. The
|
opening brace is interpreted as the start of the next argument, which
|
opening brace is interpreted as the start of the next argument, which
|
continues until a closing brace is encountered. In this case the
|
continues until a closing brace is encountered. In this case the
|
closing brace occurs on the second line, so the second argument passed
|
closing brace occurs on the second line, so the second argument passed
|
to <TT
|
to <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>cdl_option</TT
|
>cdl_option</TT
|
> is
|
> is
|
<TT
|
<TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>\n # This is a comment</TT
|
>\n # This is a comment</TT
|
>. This second argument is processed in a recursive
|
>. This second argument is processed in a recursive
|
invocation of the Tcl interpreter and does not contain any commands,
|
invocation of the Tcl interpreter and does not contain any commands,
|
just a comment. Top-level script processing then resumes, and the next
|
just a comment. Top-level script processing then resumes, and the next
|
command that is encountered is <TT
|
command that is encountered is <TT
|
CLASS="LITERAL"
|
CLASS="LITERAL"
|
>default_value</TT
|
>default_value</TT
|
>. Since
|
>. Since
|
the parser is not currently processing a configuration option this is
|
the parser is not currently processing a configuration option this is
|
an error. Later on the Tcl interpreter would encounter a closing brace
|
an error. Later on the Tcl interpreter would encounter a closing brace
|
by itself, which is also an error.</P
|
by itself, which is also an error.</P
|
><P
|
><P
|
>For component writers who need more information about <SPAN
|
>For component writers who need more information about <SPAN
|
CLASS="APPLICATION"
|
CLASS="APPLICATION"
|
>Tcl</SPAN
|
>Tcl</SPAN
|
>,
|
>,
|
especially about the language rather than the syntax, various
|
especially about the language rather than the syntax, various
|
resources are available. A reasonable starting point is the
|
resources are available. A reasonable starting point is the
|
<A
|
<A
|
HREF="http://www.tcl.tk/scripting/"
|
HREF="http://www.tcl.tk/scripting/"
|
TARGET="_top"
|
TARGET="_top"
|
>Scriptics developer
|
>Scriptics developer
|
web site</A
|
web site</A
|
>.</P
|
>.</P
|
></DIV
|
></DIV
|
><H3
|
><H3
|
CLASS="FOOTNOTES"
|
CLASS="FOOTNOTES"
|
>Notes</H3
|
>Notes</H3
|
><TABLE
|
><TABLE
|
BORDER="0"
|
BORDER="0"
|
CLASS="FOOTNOTES"
|
CLASS="FOOTNOTES"
|
WIDTH="100%"
|
WIDTH="100%"
|
><TR
|
><TR
|
><TD
|
><TD
|
ALIGN="LEFT"
|
ALIGN="LEFT"
|
VALIGN="TOP"
|
VALIGN="TOP"
|
WIDTH="5%"
|
WIDTH="5%"
|
><A
|
><A
|
NAME="FTN.AEN1270"
|
NAME="FTN.AEN1270"
|
HREF="language.tcl.html#AEN1270"
|
HREF="language.tcl.html#AEN1270"
|
>[1]</A
|
>[1]</A
|
></TD
|
></TD
|
><TD
|
><TD
|
ALIGN="LEFT"
|
ALIGN="LEFT"
|
VALIGN="TOP"
|
VALIGN="TOP"
|
WIDTH="95%"
|
WIDTH="95%"
|
><P
|
><P
|
>It is possible that some versions of the Tcl interpreter will instead
|
>It is possible that some versions of the Tcl interpreter will instead
|
produce a result of 54 when asked to multiply six by nine. Appropriate
|
produce a result of 54 when asked to multiply six by nine. Appropriate
|
<A
|
<A
|
HREF="http://www.douglasadams.com/creations/hhgg.html"
|
HREF="http://www.douglasadams.com/creations/hhgg.html"
|
TARGET="_top"
|
TARGET="_top"
|
>reference
|
>reference
|
documentation</A
|
documentation</A
|
> should be consulted for more information on why
|
> should be consulted for more information on why
|
42 is in fact the correct answer.</P
|
42 is in fact the correct answer.</P
|
></TD
|
></TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
><DIV
|
><DIV
|
CLASS="NAVFOOTER"
|
CLASS="NAVFOOTER"
|
><HR
|
><HR
|
ALIGN="LEFT"
|
ALIGN="LEFT"
|
WIDTH="100%"><TABLE
|
WIDTH="100%"><TABLE
|
SUMMARY="Footer navigation table"
|
SUMMARY="Footer navigation table"
|
WIDTH="100%"
|
WIDTH="100%"
|
BORDER="0"
|
BORDER="0"
|
CELLPADDING="0"
|
CELLPADDING="0"
|
CELLSPACING="0"
|
CELLSPACING="0"
|
><TR
|
><TR
|
><TD
|
><TD
|
WIDTH="33%"
|
WIDTH="33%"
|
ALIGN="left"
|
ALIGN="left"
|
VALIGN="top"
|
VALIGN="top"
|
><A
|
><A
|
HREF="language.naming.html"
|
HREF="language.naming.html"
|
ACCESSKEY="P"
|
ACCESSKEY="P"
|
>Prev</A
|
>Prev</A
|
></TD
|
></TD
|
><TD
|
><TD
|
WIDTH="34%"
|
WIDTH="34%"
|
ALIGN="center"
|
ALIGN="center"
|
VALIGN="top"
|
VALIGN="top"
|
><A
|
><A
|
HREF="cdl-guide.html"
|
HREF="cdl-guide.html"
|
ACCESSKEY="H"
|
ACCESSKEY="H"
|
>Home</A
|
>Home</A
|
></TD
|
></TD
|
><TD
|
><TD
|
WIDTH="33%"
|
WIDTH="33%"
|
ALIGN="right"
|
ALIGN="right"
|
VALIGN="top"
|
VALIGN="top"
|
><A
|
><A
|
HREF="language.values.html"
|
HREF="language.values.html"
|
ACCESSKEY="N"
|
ACCESSKEY="N"
|
>Next</A
|
>Next</A
|
></TD
|
></TD
|
></TR
|
></TR
|
><TR
|
><TR
|
><TD
|
><TD
|
WIDTH="33%"
|
WIDTH="33%"
|
ALIGN="left"
|
ALIGN="left"
|
VALIGN="top"
|
VALIGN="top"
|
>Option Naming Convention</TD
|
>Option Naming Convention</TD
|
><TD
|
><TD
|
WIDTH="34%"
|
WIDTH="34%"
|
ALIGN="center"
|
ALIGN="center"
|
VALIGN="top"
|
VALIGN="top"
|
><A
|
><A
|
HREF="language.html"
|
HREF="language.html"
|
ACCESSKEY="U"
|
ACCESSKEY="U"
|
>Up</A
|
>Up</A
|
></TD
|
></TD
|
><TD
|
><TD
|
WIDTH="33%"
|
WIDTH="33%"
|
ALIGN="right"
|
ALIGN="right"
|
VALIGN="top"
|
VALIGN="top"
|
>Values and Expressions</TD
|
>Values and Expressions</TD
|
></TR
|
></TR
|
></TABLE
|
></TABLE
|
></DIV
|
></DIV
|
></BODY
|
></BODY
|
></HTML
|
></HTML
|
|
|
