Lesson 6: Text Processing Commands

        This lesson introduces commands which operate upon words,
sentences, and paragraphs.  For this lesson you should have some
text to play around with, and it should have a few paragraphs. 
The text of this lesson is an ideal example, but you may want to
use some text that you have been working on and are familiar
with.  Read the file into Perfect Writer (after you've entered
the editor) with C--X C--R.  (If you decide you want to use this
lesson text, read in "lesson6".)

        The first three commands we will learn are M--U, M--L,
and M--C.  All three work on words.  M--U stands for "Uppercase
word".  M--L stands for "Lowercase word".  M--C stands for
"Capitalize word".  Try each of these on some words.    For
example, if you had the word "Macpherson" and positioned the
cursor on the "p", an M--C would  produce "MacPherson", an M--L
would leave the word unchanged, and an M--U would create
"MacPHERSON".  The word casing commands would have left the
cursor on the space following the word.  

    	Another set of useful commands allow you to transpose
characters or words.  Often typing mistakes result in characters
typed in the wrong order, such as "tpye" instead of "type".  To
correct this simply place the cursor on the second of the
transposed characters and enter C--T.  Try this now on the 
"tpye" example.  You can also correct transposed words with the
M--T command.  Practice this command on text this.  Place the
cursor between "text this" and enter M--T.  The result will
be "this text" with the cursor at the end of "text".

        The next command we will learn deals with sentences.  It
is M--K, the "Delete sentence" (or "Kill sentance) command.  M--K
is similar to C--K; it saves what it kills in case you want to do
a C--Y later.  Also, just as a C--K typed in the middle of a line
only kills forward to the end of the line, an M--K, if typed in
the middle of a sentence, will only kill from that point to the
end of the sentence.  (If you are in the middle of a sentence and
want to kill it all, beginning to end, type M--A (beginning of
sentence, learned in Lesson 2) then M--K.)

        M--K can be fooled by abbreviations because they have
periods in them and hence look just like ends of sentences.  But
better too little deleted than too much.  If M--K ever stops
before you want it to, just type it again, and the "rest" of the
sentence will disappear.  Try a few M--K's and then a Control
Y to restore it all.  You may notice that the last M--K will
not delete the two spaces after sentence punctuation.  It truly
only deletes from where the cursor is to the next end-of-sentence
which follows it.  You may have to clean up the extra spaces
manually.

        The rest of the commands we will learn about in this
lesson deal with entire paragraphs of text.  The two simplest
commands are M--P and M--N.  They move to the beginning and end,
respectively, of whatever paragraph you are in.  (You can
remember these commands because they look very similar to M--<
and M-->, which we learned in Lesson 2.)  If you are inbetween
two paragraphs and not really "in" either one, M--P will move to
the beginning of the preceding paragraph and Escape N will move
to the end of the following one.

        Try these a few times, at various places in the text. You
may notice the cursor stop in places you didn't think were
paragraphs, for example in the middle of lists or in front of
indented examples.  So, what makes a paragraph?  As far as these
and all other Perfect Writer paragraph commands are concerned, a
paragraph begins:

	(1) A blank line.

	(2) A line started by hitting the TAB key.

        (3) A line started with a commercial at-sign ("@@").  This
            is for compatibility with Perfect Writers "Document
            design" commands.

        Another command for dealing with paragraphs of text is
M--Q.  M--Q "fills" entire paragraphs of text, rearranging words
and lines so that the right-hand margin is consistent.  It allows
you to keep the text neat.  When modifying a previously existing
paragraph you may add or delete words without worrying about
existing margins, because M--Q can fix them up when you're done.

        Try filling a few paragraphs.  (To make M--Q work on a
particular paragraph, position the cursor anywhere in it, then
type the M--Q.)  If M--Q doesn't do anything to the text, then
the paragraphs are already as well filled as they can be.  Try
inserting some extra text into a line and doing another M--Q.  If
you notice M--Q joining any paragraphs together, this is because
they were not separated properly.  M--Q uses the same
paragraphing rules as M--P and Escape N do.  If you want to make
certain of how much text you are about to fill with M--Q, you can
check to see where the edges are by tpying M--P, then M--N, then
(if you're satisfied that the boundaries are correct) M--Q.

        Of course, no harm is done if M--Q joins two groups of
text which you desired as separate paragraphs.  You can easily
position yourself to where you want the new paragraph to occur
and insert the proper separator (either a blank line or a leading
tab).  Then just M--Q the second new paragraph.  Similarly, to
join and refill two paragraphs, merely delete the separator
characters and use M--Q.  This can be particularly useful for
modifying memoranda, manuals, or legal documents, where text is
frequently repositioned to change paragraph structure and
coherence.

        You may have wondered how M--Q knows where the right
margin is supposed to be.  There is a default margin column,
which you can set yourself if you choose.  The command to do this
is "C--X F".  That is, type a C--X, and then an "F".  (This
command stands for "Fill column".)

        There are two ways to use C--X F.  One is with a
universal repeat.  Type:

        C--U 70 C--X F

and you will see a message in the echo line saying "Fill Column =
70".  Try setting the fill column to something between 75 and 80
and do an M--Q.  The other way to set the fill column is "by
eye". Move the cursor to somewhere in the middle of a line, and
type C--X F without a repeat count.  You will see a new fill
column setting appear in the echo line.  Type an M--Q again and
notice where the new right margin is.  If you enter C--X F and
repeat with C--U, it will set the fill column to that number.  If
you do not, it will set the fill column to wherever the cursor is
at the time.

        Another useful command is "C--X ." (That is, a C--X,
followed by a period.)  This command sets the paragraph
indentation column, and is used to make an entire paragraph be
indented away from the left edge of the screen.  This command is
analogous to setting the left margin on a typewriter, but this
margin is used only by the Text-filling commands.  Type:

        C--U 10 C--X .

and you will see the message "Indent Column = 10" appear in the
echo line.  Type an M--Q and look at the results.

        The "C--X ." command is useful for making narrower
paragraphs, perhaps for example text or quotes.  To make one,
make the indent column larger and the fill column smaller, then
type the text and fill it with M--Q.  Then, return the fill and
indent columns to their original positions.  (The standard
settings are usually set by "C--U 0 C--X ." and "C--U 65 C--X
F".)

	If you want to continue with the next Teaching Disk,
select option  E  from the Main Selection Menu and enter
"lesson7" when asked the name of file to edit.  Use the C--X 
C--C  command to exit.
riod.)  This command sets the paragraph
indentation column, and is used to make an enti