-=[ ED - Unix Style Line Editor ]=-

The online editor is a clone of the Unix ed.  This is a rehash
of the original ed docs.  Only creators have access to the
online editor.

Ed has two modes, command mode and insert mode.  Command mode
has the prompt ':',  insert mode has no prompt.


<Insert Mode Commands>

Insert mode has only one command.  By typing a single '.' at
the beginning of the line you exit insert mode, and enter
command mode.  Otherwise, each line of text is added to the
document.


<Command Mode Command>

All commands in command mode will accept the following format,

<line1,line2>command    - apply command from line1 to line2
<line1>command          - apply command to line1
command                 - apply command to current line


For example:

:1,5d                   - delete from line 1 to line 5
:2d                     - delete line 2
:d                      - delete current line

If any numbers are out of range the command will fail.


<Commands>

Commands that use a line range:

     p         Print line.
     d         Delete line.
     l         Print line with control characters.
     r file    Read in a file after the line specified.
     s         Substitute patterns. See special documentation.
     z         Print 10 lines.
     a         Start insert mode after specified line.
     i         Start insert mode before specified line.

Commands used without line specification:

     q         Quit. Won't work if file is changed.
     Q         Quit and discard all changes if not saved.
     w         Write the file out.
     w file    Write the file out with name 'file'.
     e file    Edit a file.
     !cmd      Give a game command.
     =         print line number

     h         online ed help


<ed line reference tokens>

'.' - reference current line number.

     A '.' is the "current line". The current line is
     the last line referenced. If you want to print last line
     + 10 more:

          .,.+10p

'$' - reference last line of file

     A '$' is last line of file. Thus '1,$p' will always print
     all of the file.


<ed commands can use Regular Expressions>

     There are special characters that can be used in the
     pattern:

          .         Match any character.
          x*        Match any numbers of x (0 or more).
          [abc]     Match 'a', 'b' or 'c'.
          [0-9]     Match any digit 0 - 9.
          [a-z]     Match any lowercase letter.
          \x        Match 'x' where 'x' can be any character.


<EXAMPLES>


-=- Pattern Searching -=- </>

Change the current line to the next occurance of the pattern.    
Pattern searching can use regular expressions.

:/hello
     search for the pattern 'hello' after the current line.

:/
     repeat the last search pattern


-=- Substitute Command -=-   <s> 

First a simple example:

:s/apa/bepa/
     This will substitue the 'apa' in current line to 'bepa'.
     If an 'p' is appended, you will also immediately see the
     result.

:1,$s/apa/bepa/
     Same, but all lines in file. Only first occurence on every
     line.

:s/ab.d/ABCD/
     Substitute any string 'abXd' against 'ABCD' where X can be
     any character. (see regular expressions)

Any character can used instead of '/':

:s!apa!bepa!g
     The 'g' specifies that all occurences of apa on this line
     are changed to bepa.


-=- Read a file into current document -=-  <r>

You must have valid read access to read the file.

:r /room/church.c
     Read the file /room/church.c into the current document at   
     the current line.

:r church.c 
     Read the file church.c from your default directory.


-=- Write document to an alternative file -=- <w>

You must have valid write access to write the file.

:w church2.c
     Write the document to church2.c in you default directory.

:w /room/church2.c
     Write the document to /room/church2.c


-=- Deleting lines -=- <d>

This will delete line(s) from the document.

:d
     delete current line

:2d
     delete line 2

:2,5d
     delete from line 2 to 5


-=- Exiting ed -=- <x,q,Q>

There are 3 ways to exit the editor.

:x   
     exit and save all changes to the edited file

:q
     exit only if no changes have been made

:Q
     exit, DO NOT save changes