{!-- -USEFUL LANGUAGE EXTENSIONS--- --}
{DEF IFUNDEF {WHEN {NOT {DEFINED @0}} {SET @0 {@1}}}}
{DEF SQR {* @0 @0}}
{DEF ++ {SET @0 {+ @@0 1}}}
{DEF =+ {FOREACH VAL {REST @*}{SET @0 {+ @@0 @VAL}}}}
{DEF += {FOREACH VAL {REST @*}{SET @0 {+ @@0 @VAL}}}}
{DEF -- {SET @0 {- @@0 1}}}
{DEF =- {FOREACH VAL {REST @*}{SET @0 {- @@0 @VAL}}}}
{DEF -= {FOREACH VAL {REST @*}{SET @0 {- @@0 @VAL}}}}
{DEF NOT {?: @0 FALSE TRUE}}
{DEF SILENT}
{SET BRACE_OPEN {"\{}}
{SET BRACE_CLOSE {"\}}}
{DEF RESET {UNSET @0}{SET @0 {REST @**}}}
{DEF LEFTEXCEPT	{LEFT {- {CHARS @1} @0} @1}}
{DEF RIGHTEXCEPT	{RIGHT {- {CHARS @1} @0} @1}}

{DEF SWITCH
	{SET SW:done FALSE}
	{FOREACH line {REST @*}
		{WHEN {OR {== @0 {FIRST @line}} 
						{AND {== {FIRST @line} OTHERWISE} {NOT @SW:done}}}
			{'{EVAL {REST @line}}	{RESET SW:done TRUE}}}}
	{UNSET SW:done}
}

{DEF TSWITCH
	{FOREACH line {REST @*}
		{WHEN {{FIRST @line} @0 {WORD 1 @line}}
			{EVAL {REST {REST @line}}}}}}

{DEF ALTERNATE
	{RESET ALTERNATE:toggle {NOT @ALTERNATE:toggle}}
	{IF @ALTERNATE:toggle {'{@0}{@1}} {'{@1}{@0}}}
}

{!-- HTTP PROTOCOL HEADERS --}
{DEF HTTP_TYPE {HTEX_OUTPUT_TO_STDOUT}Content-type: @0

}

{IF {@HTEX_COMPILE}
	{'{DEF HTTP_HTML {HTEX_OUTPUT_TO_STDOUT}}
		{DEF HTTP_GIF {HTEX_OUTPUT_TO_STDOUT}}
		{DEF HTTP_JPG {HTEX_OUTPUT_TO_STDOUT}}
		{DEF HTTP_AUDIO {HTEX_OUTPUT_TO_STDOUT}}
		{DEF HTML {HTEX_OUTPUT_TO_STDOUT}}
	}
	{'{DEF HTTP_HTML {HTTP_TYPE text/html}{RESET HTTP_HTML}}
		{DEF HTTP_GIF {HTTP_TYPE image/gif}{RESET HTTP_GIF}}
		{DEF HTTP_JPG {HTTP_TYPE image/jpg}{RESET HTTP_JPG}}
		{DEF HTTP_AUDIO {HTTP_TYPE audio/basic}{RESET HTTP_AUDIO}}
		{DEF HTML {HTTP_TYPE text/html}{RESET HTML }}
	}
}

{!-- ------------------------------------------------ --}

{!-- -- FILE NAME COMPUTATION --}
{!-- -- COMPUTE THE SOURCE FILE --}

{IF {@HTEX_COMPILE}
	{SET PROGRAM_URL {WEB_URL}}
	{SET PROGRAM_URL {WEB_URL}{@HTEX_PROGRAM_NAME}/}
}

{WHEN {NOT {DEFINED PATH_INFO}}
	{IF {== {ENV REDIRECT_URL} {"}}
		{SET PATH_INFO {RIGHTEXCEPT 1 {ENV PATH_INFO}}}
		{SET PATH_INFO {RIGHTEXCEPT 1 {ENV REDIRECT_URL}}}
	}

	{WHEN {== @PATH_INFO {"}}
		{SET PATH_INFO @HTEX_COMMAND_LINE_OPTION1}
	}
}

{!-- REMOVE PREFIX --}
{FOREACH word @HTEX_PATH_PREFIXES
	{WHEN {== {LEFT {CHARS @word} @PATH_INFO} @word}
		{SET c {CHARS @word}}}}

{UNSET HTEX_SOURCE_PATH}
{SET HTEX_SOURCE_PATH {LEFTEXCEPT @d {RIGHTEXCEPT @c @PATH_INFO}}}

{WHEN {== {HTEX_SOURCE_PATH} {"}}
	{UNSET HTEX_SOURCE_PATH}
	{SET HTEX_SOURCE_PATH @HTEX_DEFAULT_SOURCE_FILE}}

{UNSET THIS_URL}
{SET THIS_URL {'{PROGRAM_URL}{@HTEX_SOURCE_PATH}}}


{UNSET THIS_PAGE}
{SET THIS_PAGE @HTEX_SOURCE_PATH}
{SET THIS_DIR @HTEX_SOURCE_PATH}
{SET HTEX_SOURCE_DIRECTORY @THIS_DIR}
{SET THIS_PATH @HTEX_SOURCE_PATH}
{SET STD_BASE {WEB_URL}{@THIS_PATH}}

{!-- ----------------------------------------------- --}


{DEF KEYWORDS 
	<META Name="keywords" CONTENT="{FOREACH word @* {'{@word}, }}">
	<!-- KEYWORDS: {FOREACH word @* {'{@word}, }} -->
}


{!-- HEADING --}
{SET HEADING:color {RANDOM 2 7}{RANDOM 2 7}{RANDOM 2 7}{RANDOM 2 7}{RANDOM 2 7}{RANDOM 2 7}}


{!-- ----------------- --}
{DEF HEADING
	{!-- DEFAULTS --}
	{SET heading_em <EM> </EM>}
	{SET heading_h <H2> </H2>}
	{SET heading_line <hr>}
	{SET heading_lift +2}
	{SET heading_color TRUE}
	{FOREACH setting @1 
		{SWITCH @setting
			{"NOEXTRAS  {SET heading_em }{SET heading_h }{SET heading_color FALSE}{SET heading_line }}
			{"NOCOLOR  {SET heading_color FALSE}}
			{"NOLINE  {SET heading_line }}
			{"NOSIZE {SET heading_h }}
			{"TIGHT 	{SET heading_h <H3> </H3>}	{SET heading_line }	{SET heading_lift +2}}}}

		{FIRST @heading_h}
		{FIRST @heading_em}
		{WHEN @heading_color	<FONT COLOR={@HEADING:color}>}
		{FOREACH word @0 
			{SET capword {CC:UPPER @word}}
			{IF {== {LEFT 1 @capword} +} 
				{'<FONT SIZE={@heading_lift}>{RIGHTEXCEPT 1 @capword}</FONT>}
				{'{WHEN {!= {LEFT 1 @capword} _} 
						<FONT SIZE={@heading_lift}>{LEFT 1 @capword}</FONT>}{RIGHT {- {CHARS @capword} 1} @capword}&nbsp;}
			}
			{UNSET capword}
		}

	
		{WHEN @heading_color	</FONT>}
		@heading_line	
		{FIRST {REST @heading_em}}
		{FIRST {REST @heading_h}}
}


{DEF LINKTO <A HREF="{@0}">{IF {GT @PARAMS 1} @1 @0}</A>}

{DEF SETCOOKIE {HTEX_OUTPUT_TO_STDOUT}Set-Cookie: {@0}={@1}; path=/; domain=ai.mit.edu; expires=Monday, 27-Oct-99 06:48:50 GMT
{HTEX_OUTPUT_TO_NULL}}

{DEF RESETCOOKIE 
	{FOREACH OPT @*	{WHEN {DEFINED @OPT} {SETCOOKIE @OPT @@OPT}}}}

{DEF SELECTOPTIONS
		<SELECT NAME="{@0}">
		{FOREACH OPT {REST @*} 
			<OPTION VALUE="{FIRST @OPT}" {WHEN {== @@0 {FIRST @OPT}} selected}>{IF {GTE {WORDS @OPT} 2} {EVAL {REST @OPT}} @OPT}}
		</SELECT>}

{DEF PASSHIDDEN 
	{FOREACH OPT @*
	<INPUT TYPE=HIDDEN NAME={@OPT} VALUE={@@OPT}>
}}