Rit version 1.2

	Rit is a PHP like language that is designed for use in Plan 9.
	The name came from "rc in text"

	You can examine Rit by processing this text:
		rit readme
	and compare the output with this file.
	You will find Rit manual in my web page:
	http://plan9.arichi-u.ac.jp/pegasus/eman-2.1/
	or if you want Japanese manual:
	http://plan9.arichi-u.ac.jp/pegasus/man-2.1/

	-Kenar- (Kenji Arisawa)

	E-mail: arisawa@aichi-u.ac.jp

General rules
Dollar '$' is only one special symbol of Rit.
A dollar followed by:
variable
	Variable is a sequence of alpha or numeric or '_'.
	subset of environment variable.
'{'
	Rc script follows. the script continues up to '}'.
	The terminator '}' must be out of rc string and out of { .. } nest.
'\n'
	NL (new line) escape

Example 1	command execution
	A dollar followed by '{':
	You can write rc script in curly brace { }
	Date: Fri Dec 24 19:31:08 JST 2004

	Note that we have redundant empty line after this command;
	this comes from two subsequent '\n's:
		one from command and one from our this text line.
	Avoiding this problem we have:
	Fri Dec 24 19:31:08 JST 2004
 continues nest line
	Fri Dec 24 19:31:08 JST 2004 continues same line.
Example 2	variable
	A dollar followed by alpha or numeric
	User: arisawa
	This is equivalent to
	User: arisawa
Example 3		NL escape
	A dollar at the end of line is NL escape.
	Example: This line has NL escape 	next line.
	Many rc command produce NL at the end
	We can avoid redundant NL by putting NL escape:
	/usr/arisawa/src/pegasus-2.1/rit
	is current working directory.
	/usr/arisawa/src/pegasus-2.1/rit	this line stays in ${pwd}$$ line.
Example 4	multi-lines
	Rit has full functionality with rc.
	For example Rit allows multi-line script:
		echo test of multi-line:
	line1: Carrol's book:
	line2: Alice in Wonder Land
	line3: and we can use { and } in rc strings
	Back slash new line escape in Rc command will work:
	one two
Example 5	'if' statement
	We have 'if' statement:
	ARISAWA
Example 6	braces in Rc
	Switch statement.
	Note that { } is included in this example.
	ARISAWA
Example 7	comment in Rc command
	Comment continues up to NL as Rc does.
	 # invisible
	 # invisible
	${# This isn't a comment but a part of text }
Example 8
	readme is special, this is a file name currently processed.
	Dollar followed other characters is not a special. i.e.,
	$, $#
	are shown as it is.
Example 9
	Sequence of dollars are processed as follows:
	If the sequence is followed by alpha or '{' or '\n'
	one dollar is simply discarded:
	$$$home is equivalent to $$$home
	$$${not a rc script}
	$$$
	is not a NL escape.
	If the sequence is followed by other characters,
	they are shown as it is:
	$$$$ is shown as four dollars
Note on termination