MicroEmacs 4.00 - A Review
By Tim Swenson
MicroEmacs is a text editor that is available on many different
computer platforms. It was originally written for Unix, but it
has migrated to MS-DOS, Windows, Mac, ST, Amiga, CP/M, and QDOS.
The earliest port that I am aware of was done of MicroEmacs 3.8.
Then versions 3.9 and 3.11 were ported. Thierry Godefroy has
taken the source of the latest version of MicroEmacs, 4.00, and
ported it to the QL. Unlike the previous ports, Thierry has added
a number of QDOS features that make the end editor much more
usable.
I first started using MicroEmacs when I wanted an editor that
could be used on the same file on different platforms. MicroEmacs
was about the only editor on the QL that was available on other
computers. It was not the easiest editor to learn. The commands
were a bit cryptic, the terms were different, and overall a bit of
a struggle. I started using it only knowing just enough commands
to get done what I needed to get done.
Editing Power
MicroEmacs has all of the basic text editing fuctions, including
marking text, deleting marked text, copying marked text, saving
mark text to a file, importing a file, and search and replace.
MicroEmacs can edit and display more than one file. Each file is
loaded into a buffer to edit. Each buffer can be displayed in a
seperate window. There are commands to create new windows, jump
between windows, resize windows, and delete windows.
MicroEmacs has various modes that it can work in. The modes are:
ABBREV - Saves typing by automatically expanding known
abbreviations to full words. Some abbreviations are built-in, but
more can be added.
ASAVE - Automatically saves files after so many characters have
been changed (added or deleted).
CMODE - Adds a number of features to help programming in C,
such as autoindentation, show matching open brace ({) when close
brace (}) is typed, and a # sign with leading white space will be
left flushed (for preprocessor directive).
CRYPT - The file edited is encrypted for saves and decrypted
for reading, based on a user given encryption key.
OVER - Overwrite mode.
WRAP - Turns on word wrap. The right margin is defined by the
user.
VIEW - Read-only mode.
I found that when using the WRAP mode, MicroEmacs is not a bad
word processor. The reformat command lets you reformat a
paragraph after it's been edited.
One feature that I really have not used is Undo. A number of
commands are kept in memory (user configurable) and you can undo 1
or more commands. You can even list the past commands.
Since MicroEmacs came from a Unix backgroud, it can "shell" out to
the operating system. Since the QL does not have a shell to
execute, the built in default is to run Adrian Ives Shell "sh".
This will allow you to do QDOS-like commands, like listing the
directory of a disk. You can also run/exec a program from within
MicroEmacs. You can edit a C program and then run the compiler
from within MicroEmacs.
Macro Language
The most powerfull feature of MicroEmacs is having a macro
langauge. Other editors have ways to automate tasks. ED/QED
allows you to enter a list of commands and it will execute them,
even repeatedly. MicroEmacs allows all this, plus it supports IF
statements and WHILE loops. All of the MicroEmacs commands have a
name, so every command is available for use in a macro. Here is
an example of what a macro looks like:
store-procedure get-word
set $kill ""
!force next-word
set-mark
!force end-of-word
copy-region
set %word $kill
; write-message &cat "The Word is : " %word
!endm
This procedure goes to the next word, marks it, and then copies it
into the "kill" buffer.
Macros can be stored in a file and executed by reading the file
in, or you can create procedures, read them in, and call then
whenever you need them. You can even bind your procedure to a key
sequence so that it is run when you enter the sequence.
MicroEmacs is really driven by the commands and not the keyboard.
The various commands are binded to a particular keyboard sequence.
Since only the commands themselves perminate, you can change the
keyboard commands to suit your prefered setup. If you want to
change the save-file command from CTRL-X-CTRL-S to CTRL-S, you
can. This allows MicroEmacs to "emulate" virtually any editor.
On the MicroEmacs web page there is a macro file that make
MicroEmacs behave like the popular MS-DOS editor, BRIEF (which I
believe is based on older WordStar commands).
MicroEmacs has a configuration file called emacs_rc. This file is
nothing more than a macro file with some pre-defined
configuration. You can put in your own procedures or you can
totally change the configuration. The only thing special about
this file is that MicroEmacs looks for it upon starting.
QDOS Support
Thierry has added a lot to MicroEmacs to make it work better in
the QDOS environment. He has added support for Toolkit II,
Pointer Environment, Menu Extensions (QMENU), Environment
Variables, QPAC2 (for buttons), FileInfo II, and QTYP II. Not all
of these extensions are need to run MicroEmacs, it checks to see
which extenions are resident and only uses those that are present.
The biggest addition is Pointer Environment menus. Most of the
MicroEmacs commands can be executed by selecting them from a menu.
Without the menus, you have to memorize a number of cryptic
commands. The commands are still there, but the menus make them
almost useless.
With Environment Variable support, you can change the
configuration of MicroEmacs for QDOS specific features. A list of
paths can be put in the PATH variable for MicroEmacs to search for
files. SHELL defines which shell you want to use. EMACS_POINTER
defines what type of pointer (hand or cursor) to use. EMACS_HOME
defines where the emacs_rc will reside (this was a variable
Thierry put in at my request).
I am not a user of FileInfo II, so I can't really explain exactly
how MicroEmacs interfaces with FileInfo II. Since Thierry is also
the author of FileInfo II, I'm sure that it interfaces well.
If you have the Menu Extensions loaded then you can copy text
to/from MicroEmacs and the scrap. This allows you to transfer
text to/from other applications.
With QTYP II, the SPELL mode is usable. It allows for real-time
spell checking or the use of the "spell-check" command, which
spell checks words in the current buffer. This feature was only
just recently added. Theirry expects to expand it and make it
more usable. Personally, I really like the ability to run spell
checking in an editor after I've type the text. I find real-time
spell checking a bit of a pain. The interruption of spell
checking throws off my train of thought.
Thierry has even made the mouse implement some MicroEmacs
commands. Besides moving the cursor around, using the right mouse
button to drag across text, the text is highlighted and put into
the "kill" buffer. The kill buffer is a temporary place to store
text. The text can then be copied from the kill buffer into the
current buffer (by again using the right mouse button). This is
how MicroEmacs does cut & paste.
Running MicroEmacs
Since I've been using MicroEmacs for a while, setting it up and
running it was fairly easy. I'll explain the steps here to assist
someone new to MicroEmacs.
The MicroEmacs zip file is fairly large. It contains the
executable, the configuration file, some command file, and the
source code. The whole package needs a hard disk or ED disk to
unzip to. If you are proficient with unzip or have ACP, you
should be able to unzip only the portions you need. It would be
nice to have just a zip file of only the parts necessary to run
MicroEmacs, as most people don't need the source code.
The primary files needed for MicroEmacs are:
emacs - The executable
emacs_rc - The configuration file
There are a number of command (_cmd), macro, files that are
mentioned in the configuration file, but unless you these
commands, they are not really necessary. In fact, you can edit
the emacs_rc file to take any reference out.
You should put the emacs executable in a directory for other
executables (defined by PROG_USE). I'm using a RomDisq, so I put
MicroEmacs in the directory ROM1_EDT_. I use the PTH device and
have PROG_USE set to PTH1_ with ROM1_EDT_ stored in the PTH. I
have also put the emacs_rc in ROM1_EDT_.
MicroEmacs firsts checks DATA_USE then PROG_USE when searching for
the emacs_rc configuration file. Since I had the file in the
PROG_USE directory with DATA_USE defined to FLP1_, MicroEmacs
would first look at FLP1_ for the file and then look in ROM1_EDT_.
If I did not have a floppy in the drive, this would add about 5
seconds to the start up time. After some heavy hinting, Theirry
added the EMACS_HOME environment variable. MicroEmacs now checks
to see if this variable is set. If so, it checks the directory
there for the configuration file. If not, it defaults back to
it's old behavior. Now MicroEmacs comes up much faster. I
quickly added :
setenv "EMACS_HOME=rom1_edt_"
to my BOOT file.
If you unzip MicroEmacs to a floppy and execute it there, it
pretty much works "right out of the box". You can then configure
it all you want. The emacs_hlp file is the QDOS README file and
covers all of the features of the QDOS version. Also included in
the zip file is the original MicroEmacs documentation. It
explains how to use and configure MicroEmacs. Expect to read a
bit before attempting to really configure MicroEmacs. With power
comes complexity.
My Impression
As a user of MicroEmacs for a number of years, this version of
MicroEmacs is big jump in usability. MicroEmacs was a powerfull
editor that was anywhere from kind of hard to fairly hard to use,
depending on what you wanted to do. The addition of menus makes
it easy to use. I have been wanting to do more with MicroEmacs
macros, but found it a bit confusing to figure out how to execute
them. This was due mostly to the key the "execute-file" command
was bound to. It was very unobvious to me how to get it to work.
A few months ago I sat down, banged my head against the wall,
until it sunk in. Then Theirry came out with this version and
suddenly it was so easy to just select the command I wanted from
the menu.
With all the new features and such, I did find that this port of
MicroEmacs to be slower, in screen handling, than over versions.
I have attrubited this to the overhead needed by the Pointer
Environment support. It takes a few extra cycles to scan for
mouse movement. When executing commands I have not noticed any
slowness. If you have MicroEmacs execute a couple of commands
from a macro, it's very fast. I wrote a macro to do some search
and replacing, printing out some text to the message line between
each search. The text flashed by on the message line so fast I
could not read it.
Your Impression
Your opinion of MicroEmacs will depend on a number of factors.
Depending on the level of complexity you like, you may find
MicroEmacs harder to run than other QL editors. If you have a
basic QL system (non-(Super)Gold Card), you may find MicroEmacs
kind of slow, when compared to an editor like QED (which I believe
was written in Assembly).
I would not recommend MicroEmacs to anyone that is not willing to
spend some time to learn the powerfull features. If you are
comfortable with your current editor and it satisfies all your
needs, then MicroEmacs may not benefit you. If you are looking
for more capability from your editor, then MicroEmacs is probably
something worth looking into.