Parity's Code Class 201

A MUSHCoding 201 class which expands on topics discussed in Parity's first class.

Author: Parity@OGR
Category: Softcode
Commands: @adrop, @emit, @pemit, @switch.
Functions: hasflag(), iter(), lwho(), switch().

MUSHCode for Parity's Code Class 201

©2000 Parity@OGR. You may copy and redistribute this document provided that it remains
complete, with credits intact, and is used only for non-profit purposes.
Parity starts logging and calls the class to order. "Speak now if you want to be edited
out of the log or forever hold your peace. ;o"
Dunross chuckles, "I'm cool with it."
Moth is cool
Parity says "Dunross, you don't already have an object. You'll need one for the practical
parts of class. Make one with '@create <some object name>' and then '@lock/uselock <some
object name>=me' and '@set <some object name>=visual'"
(post-log addendum: also, @set <some object name>=commands)
Dunross nods.
Parity says "Visual lets me see what you've done, and the uselock means only -you- can
trigger the commands you put on the object, which is helpful if we all create a command
with the same name. :)"
Dunross nods.
Moth grins
Dunross finishes.
Dunross says "Okay, I changed it to a gondola."
Moth lafs
Moth almost did that
Dunross chuckles, "might as well."
Parity says "Okee, in the last class I introduced $-commands in a kind of 'do this' way,
and we created commands by making attributes like, '&my-cmd myobject=$command:@pemit
Dunross nods.
Parity says "Everybody understand that?"
Dunross nods, has done that a lot.
Moth noddles
Parity nods, "Good. :) Now, you can do more with commands than that, as you might have
noticed. Commands often take arguments, like '+finger <some name>'
Dunross says "So +finger is basically a command string with a lot formatting in the emit?"
Parity nods, "That's precisely it."
Moth says "Ahhhhhh"
Dunross nods, "Okie. Huh."
Parity says "Now, the way we get arguments into our command is pretty simple. When we
make a $-command, we can put a '*' anywhere we want to allow arbitrary text."
Parity says "For example, '&echo-cmd myobj=$echo *:@pemit %#=You typed '%0'.' will create
an 'echo' command that will tell you what you typed."
Parity invites everyone to try making a command like that.
Moth says "Is that what folks do to have a pemit that 'so and so just looked at you'?"
Moth says "Basically?"
Parity says "Not quite. That's more like the drop/adrop/odrop example from last class.
There's a set of those attributes, desc/adesc/odesc."
Dunross says "Oh, did I need to se my object COMMANDS?"
Parity says "Desc is what people see when they look at you, obviously."
Moth nods... wasn't sure if it was similar or not
Parity says "Adesc is an arbitrary action that happens when somebody looks at you."
Moth says "Oh yeah you do, Dun"
Dunross nods.
Parity says "So, '@adesc me=@pemit me=%n just looked at you.' does that."
Moth says "Ah okay... thanks;)"
Dunross ahs!
Dunross gets the gondola to speak!
Moth lafs
Parity grins.
Parity says "If you can drop your objects so I can see your work..."
Dunross nods.
Moth sets Prospero down.
Dunross dropped gondola.

ECHO-CMD:$echo *:@pemit %#=You typed '%0'.

Prospero wiggles his way across the floor in search of raisins.

ECHO-CMD:$echo *:@pemit %#=You typed '%0'.

Moth grins
Moth offers Prospero a raisin.
Parity nods, "Okee. Now, you don't have to limit yourself to a trailing '*' that gets put
into %0. A lot of the time you want a command that takes two arguments, like '+mail
Parity says "That's easily handled, with a command like "$twoargs *=*:@pemit #384=You
claim that '%0' is equal to '%1'." ..."
Parity invites everyone to try that.
Parity says "Err."
Parity says "With %#, not my dbref. :)"
Moth grins, you sure?;)
Parity is sure. :)
Dunross says "Do you have to do the & part for the attribute?"
Parity nods, "Sorry, I was doing shorthand... what I typed was only the value. You need to
do '&some-attrib myobj=... '
Parity digresses, "You should pick an attribute naming scheme and stick to it. I use
'some-cmd' 'some-fn' and 'some-data' ; other people prefer 'cmd-something' 'fn-something'
'data-something' etc; others prefer '.' to '-'; I advise against '_' because it requires
a shift key which makes it annoying to type repeatedly.
Dunross is confused.
Parity backs up.
Dunross looks at his object.
Parity says "When I said, '$twoargs *=*:@pemit %#=You claim that '%0' is equal to '%1'.'
I meant that as the value that goes into an attribute."
Parity says "You get that value into an attribute with something like,"
Parity says "&twoargs-cmd myobj=$twoargs *=*:@pemit %#=You claim that '%0' is equal to
Dunross nods, fixes.
Parity's digression means, it's just as valid to say, '&cmd.twoargs myobj=...'
Dunross can't get anything to emit?

TWOARGS:$twoargs *=*:@pemit %#=You claim that '%0' is equal to '%1'.
TWOARGS-CMD:$twoargs *=*:@pemit %#=You claim that '%0' is equal to '%1'.

Moth isn't sure what the trigger is
Parity says "type 'twoargs one=1'"
Dunross says "Ah..."
Moth says "Oh:)"

TWOARGS-CMD:$twoargs *=*:@pemit %#=You claim that '%0' is equal to '%1'.

Dunross says "Okay, I couldn't figure out what the syntax to use it was."
Parity says "Dunross probably sees it twice, because he has both a 'twoargs' and a
'twoargs-cmd' attribute."
Dunross says "I got rid of the other. ;)"
Parity nods, "The * can be replaced by any arbitrary text, but everything else in your
command, that is, between the '$' and the ':' needs to be literal.
Dunross says "So, is 'twoargs' something special or just the word you used?"
Dunross nods, sees now.
Dunross says "Okay, so it's up to the : not the ="
Parity says "So, if I have a command like, '$foo * and bar *:...' it needs to be
triggered with something like 'foo is 2 and bar is 7'"
Parity nods.
Parity says "It gets confusing. Let's break it down."
Moth nods, is all in favor of that
Parity says "&mything-cmd myobj=<stuff>"
Parity says "That part sets the attribute to whatever <stuff> is."
Dunross says "Right-o"
Parity says "<stuff> in a $-command, looks like '$<command format>:<command actions>'"
Dunross says "Right."
Moth nods
Moth follows!
Parity says "<command format> looks like any arbitrary text, with * being special."
Parity says "Like, 'twoargs *=*'"
Dunross nods.
Moth nods
Parity says "<command actions> looks like any string of commands that you can put in an
@adrop or the like, and sort of like any string of commands that you can type direct into
the mush."
Parity says "The problem is, MUSH does -not- treat things typed directly exactly the same
as things in commands."
Dunross says "Right, Moth, it's how the travel emits are done that we do."
Moth says "Oh yah"
Parity says "This makes life difficult sometimes, but, basically, -always- test your code
by making it into a command."
Dunross nods.
Parity says "'cause if you get a long string of code working typed directly, and then it
breaks when you make it a command, you're going to be one not-happy camper."
Moth says "Okie..."
Parity speaks from experience. ;)
Dunross says "So &<attname>-cmd <object>=$<command string>:<command action>"
Parity nods.
Moth coolbeans
Dunross says "And command action is anything you can do normally, with @commands?"
Parity says "Though, it's actually '&<attname> <object>=$<command string>:<command action>
... attname -can- be anything, I just recommend a '-cmd' suffix so you can easily do things
like 'exa myobj/*-cmd'"
Parity nods to Dunross, "Exactly. :)"
Moth says "Like @emit, @oemit, etc... like the ferret...@pemit, etc..."
Dunross says "I guess and things like iter(), but that's hwere I draw the line."
Dunross noddles, "i see."
Moth nods, gets it...
Dunross nods on <attname> being anything but -<suffix> being useful.
Parity says "iter() is a function, not a command."
Moth is using &blah-cmd...
Dunross nods, is scared of functions.
Moth nods, iter() is cool
Parity says "If I oversimplify and ignore the exceptions, a function is simply a
specially-formatted bit of text that gets replaced with other text."
Dunross says "Well, I don't mean to get you off if you had a syllabus. :)"
Parity is going to cover switch() .. .which is a function... and @switch... which is
a command, so by the end of to-day you'll know the difference. :)
Moth says "Oh good..."
Dunross says "Oh, great. cool."
Moth would like to see a real-live application of a function() <like iter, which was
cool, but I'm not sure what it would be used for practically>...
Moth woos... lets you get back to beeswax;)
Parity says "iter() is used whenever you want to do the same thing to more than one
piece of data, which happens a whole lot. Turning lwho() into a +who, getting all
the titles from a bboard group or a notebook, etc."
Moth nods, cool
Parity says "Okay. So, one thing we see a lot, is a set of commands like, '+ch/who'
'+ch/list' '+ch/join' '+ch/leave'"
Dunross nods.
Moth nods
Parity says "THere's two ways to do this. The simple way, that you should use whenever
you can, is to create multiple commands."
Parity says "We create a command like, '$+various/first *:@pemit %#=You typed '%0'.'
and another, '$+various/second *:@pemit %#=Flag was second, input was '%0'.'"
Parity says "To the user, it -looks- like one comand '+various' that is called with a syntax
of '+various/<flag> <input>'"
Moth says "And the attribute portion is always the same syntax-wise..."
Moth says "Or is this something different?"
Parity says "And if we carefully make another command, '$+various *:@pemit %#=Basically:
%0', because -this- command has a space after the word 'various' it will never be mixed
up (by the mush parser) with the '+various/' commands."
Parity says "You should store each command in its own attribute."
Parity says "I usually use something like, '&various-first-cmd' '&various-second-cmd'
Moth says "Oh, good, that's what I was about to do"
Parity says "Which gets some pretty unwieldy names, but makes it easy to find things with
exa myobj/various-*-cmd"
Dunross blinks, is still rereading. :P
Parity gets some coffee and pauses for questions.
Moth has the three set. Now what would these be used for?
Dunross says "Okay, so that's a series of various commands, but what does $various *:
return? just the list of options of various/flags?"
Parity says "Whatever you want. :o"

VARIOUS-SECOND-CMD:$+various/second *:@pemit %#=Flag was second, input was '%0'.
VARIOUS-FIRST-CMD:$+various/first *:@pemit %#=You typed '%0'.
VARIOUS-BASE-CMD:$+various *:@pemit %#=Basically: %0.

Moth says "If I type +various prospero, I get: Basically: prospero"
Parity nods.
Parity says "In this example, they all just @emit."
Moth says "b/c I used Basically: %0"
Moth nods
Parity says "In the channel case, you would have '+ch/who *' '+ch/join *' '+ch/leave *'
and '+ch *=*'"
Moth ahhhhhs
Moth says "Instead of +various/first, etc"
Parity says "Where /who pemits a who list, join adds you to the channel, leave removes
you from the channel, and *=* speaks text onto a channel."
Parity nods. :)
Moth says "Oh:)"
Parity says "+various is just an example of how to use a command/flag syntax."
Parity says "It doesn't actually -do- anything. ;)"
Parity says "Everybody clear now?"
Dunross ahs.
Moth says "So it'd be, as an example: &channel-who-cmd=$+ch/who *:@pemit #386=<whatever>"
Parity nods, "Except you meant to type %%# to escape the substitution, but yes.
Moth says "Yah;)"
Moth says "Okay!"
Parity says "Dunross, you clear now?"
Dunross says "Yeah, I think so. That's how you get +ch/flags. They're really separate
commands, where the /flag is included in the $-command?"
Parity nods, "Almost always, yes."
Dunross says "But to the user, it transparent."
Parity says "Precisely!"
Dunross <---is the cerebral one. :P
Moth snorts
Dunross says "And then for something like channels, all the commands reside on the same
object, say like Channel Object?"
Moth says "to the user, everything is transparent..."
Dunross says "Well, this is true."
Moth <--- is the existential one
Parity nods, "If I oversimplify, yes. ;) That's how it used to be, anyway, but these
days channels are usually built into the MUSH. (On TinyMUX, TinyMUSH3.0 and PennMUSH).
Dunross says "Right."
Parity says "We're on a 2.2 here though, so that's probably exactly how it is done."
Dunross nods.
Moth nods
Parity is going to digress now. :)
Moth lafs
Moth says "Okay;)"
Parity says "We're going to discuss the 'hasflag()' function."
Parity says "Everybody try 'say hasflag(me,connected)'"
Moth says "1"
Parity says "Then try, 'say hasflag(*gorgo,connected)'"
Moth says "0"
Dunross says "1"
Dunross says "0"
Dunross says "1=yes. 0=no."
Parity says "If it isn't yet obvious, what is happening is that 'hasflag()' is a function,
and it gets replaced with '1' or '0' depending on the test."
Dunross nods.
Moth nods
Parity nods, "1 for yes, 0 for no, in this particular case, we're testing for the
'connected' flag, and now, if we didn't know it before, we know that we all have the
connected flag, and Gorgo doesn't.
Dunross nods.
Dunross says "Cool."
Parity notes the '*' before a name is to make sure that MUSH understands 'this is
a player name' so it looks at the player-list instead of the objects in the room.
Moth nods
Moth says "Cool..."
Dunross nods. "That's the same issue when you are ex'ing someone from another room?"
Parity says "If you do 'hasflag(gondola,connected)' it will check your inventory and
the inventory of the room you're in, find the 'gondola' in this room, and then inform
you that it does not have a connected flag, which isn't suprising - only players ever
have a connected flag."
Parity nods to Dunross, "Exactly."
Moth nods...
Dunross nods on the flag.
Parity proceeds to introduce the 'switch()' function...
Dunross says "1"
Dunross says "Moth is connected. :)"
Moth gasps!
Parity says "Sometimes, we don't want to do exactly the same thing every time we execute
a sequence of code."
Parity says "switch() and @switch take care of this for us."
Moth ahhhhhs
Parity says "'switch(1,1,yes,0,no)' will turn into the word 'yes'"
Parity says "'switch(0,1,yes,0,no)' will turn into the word 'no'"
Dunross says "ooh. That's scary."
Parity says "'switch(hasflag(%0,connected),1,yes,0,no)' might become yes or no depending
on what 'hasflag()' becomes..."
Moth hmmmmms
Parity says "Using *, we can do 'switch(hasflag(*%0),...)' and always get a player, and
make a command to check whether or not someone is connected."
Parity asks you all to try that, and ask questions if you're not sure how.
Dunross says "Can you say again what returns?"
Dunross says "Oops. //"
Moth says "We 'say' that right?"
Dunross says "%0"
Dunross says "Okay. Can you say again waht %0 does again?"
Moth says "..."
Moth says "oops;)"
Parity says "Okay, '%0' will contain whatever was in the first '*' in a command description."
Parity says "%1 will contain whatever is in the second '*', and %2 the third *, and so
on, up to %9 containing the tenth *."
Moth hmms
Dunross says ""
Moth thinks I got lost somewhere, but isn't sure where. **scrolls and rereads**
Parity says "Like, in 'echo-cmd' we had '$echo *:@pemit %#=You typed '%0'' ..."
Dunross says "..."
Parity says "The %0 was replaced with what we typed in the place of the *."

ECHO-CMD:$echo *:@pemit %#=You typed '%0'.
TWOARGS-CMD:$twoargs *=*:@pemit %#=You claim that '%0' is equal to '%1'.

Parity says "In, 'twoargs-cmd' we had '$twoargs *=*' and what was typed in place of the
* before the equals got put into '%0', and what was typed in the place of the * after
the equals got put into '%1'."
Parity says "Making sense now?"
Moth says "Yeah, that part does... I'm hung up on the switch bits"
Parity ahhhs.
Dunross says "Okay, can we go back to switch(1,1,yes,0,no)? I don't understand the
commad syntax, maybe that's it. What are the 5 arguments saying in the ()?"
Dunross d'ohs.
Moth says "When I do: say switch(hasflag(*%0),...), I get: "..." but not a player..."
Parity says "Okay. switch(). switch(<value>,<conditional-value-1>,<on-condition-1>,
Parity ohhhs, "Sorry."
Parity says "By '...' I meant, 'What I typed before'"
Moth says "Oh...laf... sorry"
Moth takes this stuff very literally.
Parity says "But when you 'say switch(hasflag(*%0),0,no,1,yes)', %0 will actually
(Post-lecture addendum: Actually, this is a little bit of a confusing situation. If I
'say switch(hasflag(*%0),0,no,1,yes)' %0 will actually be 'switch(hasflag(*),0,no,1,yes)'
because the %0 in what I say gets evaluated with %0 being 'nothing' and -then- what's left
gets passed to say. Anyway. Don't worry about it, it's only a curiousity, the point is,
don't 'say' things with %0, %1, etc, in them.)
Dunross says "switch(hasflag(*,connected)"
Parity says "Because the 'say' command has a syntax of '$say *:<stuff>'"
Parity says "You need to use %0 only in commands."
Moth says ""
Parity says "If you're going to 'say' things, try, 'say switch(hasflag(*dunross),0,no,1,yes)'"
Moth says ""
Parity hms.
Moth says "Weird"
Dunross says ""
Moth is saying switch(hasflag(*dunross),0,no,1,yes) and gets ""
Parity expands on switch, "switch can also take a 'default' argument... if it didn't match
any of the previous tests, it will evaluate to the default."
Parity hrms.
Parity says "Oh. Duh."
Parity says "hasflag(*dunross,connected)"
Moth ohs;)
Parity was typing too fast.
Moth says "Okay!"
Parity says "yes"
Moth says "yes"
Dunross says "Right. I got that part. hasflag(*dunross,connected)"
Dunross says "It's after that that I'm still sorta lost. ;)"
Moth says "Okay, I -sort- of get it, but I don't want to slow you down... I'll reread it
Parity wants people to understand switch().
Parity says "That's one of the main goals of this class."
Parity says "If you don't understand, people reading the log might not understand."
Parity says "Okay, let's do this."
Parity says "Make a command, '&myswitch-cmd <myobj>=$myswitch *:@pemit %#=You entered a
value [switch(%0,0,zero,1,one,2,two,bigger than two)]."
Dunross nods.
--> myswitch 0
You entered a value zero.
--> myswitch 1
You entered a value one.
--> myswitch 2
You entered a value two.
--> myswitch 3
You entered a value bigger than two.

Parity says "Now, try 'myswitch 1'"
Dunross ahs.
Parity says "Try, 'myswitch 19'"
Parity says "And try, 'myswitch 0'"
Dunross says "Switch is like an if-then?"
Parity nods! "Exactly! :)"
Parity says "Actualy, it's like an 'if-then-else-if-then-else-if-then-else... '"
Dunross says "Oh, well, why didn't you just say so? ;)"
Parity didn't want to assume anyone knew other programming languages.
Dunross noddles. "Understandable."
Moth doesn't;p
Dunross figures that's just logic?
Parity says "But it is like 'if-then-else', or more accurately, like a C 'switch/case'
or a pascal 'case'."
Moth nods
Moth says "If it's %0 or 0 then zero... if it's 1, then one... I "roundly" get it."
Moth says "Which is what I understood from the <condition>,<conditional> bits"
Parity says "So, it says, 'if 0, then return 'zero', else if 1, return 'one', else if 2,
return 'two' else return 'bigger than two'"
Moth nods
Dunross says "Right. The %0 is still throwing me, but that's alright. dunno why it is."
Parity says "And the value being compared to in each 'if' is the first argument of the
Dunross says "Ah..."
Parity says "%0 is simply replaced with what you put in the place of the '*' in the
command syntax."
Dunross ahs and nods.
Moth says "So ... because %0=no...that's what all that was about"
Dunross says "That's the part of myswitch *=*"
Moth follows
Dunross says "What Moth said."
Parity says "So, when I do 'myswitch 1' then 'switch(%0,0,zero,1,one,2,two,bigger than
two)' becomes,"
Parity says "switch(1,0,zero,1,one,2,two,bigger than two)"
Parity says "Which in turn, becomes,"
Parity says "one"
Parity says "And then 'one' gets put into the string that is being @pemitted in the
myswitch command."
Parity says "Is that clear?"
Dunross is still examining. :)
Moth nods, thinks I have it
Moth says "More or less"
Parity says "Okay."
Moth chuckles
Parity says "Why don't you try tackling the exercise again - create a command that uses
switch to @pemit 'yes' if someone is connected and 'no' if they're not."
Dunross says "Okay. So, it says for 0, zero. For zero, it say 'a value bigger than two'?"
Dunross says "That's cause it doesn't know 'zero' for the %0?"
Parity nods to Dunross, "That's because we're checking explicitly for '0' '1' and '2'. We
assume anything else is a value bigger than two, and return 'bigger than two'.
Dunross nods.
Parity says "If you change the switch to not have the 'default' case of 'bigger than
two' you'll just get 'A value .'"
Parity says "This is what we call non-robust code. :)"
Parity says "We didn't check to make sure that %0 was even a number before doing our
Parity says "This kind of thing is why MUSHcode commands sometimes return confusing
things if they weren't well written, and why, if you read a well-written MUSHcode
command, it always seems really complicated."
Moth hmms...
Parity notes MUSHcode is a bad, bad, horrible, evil, twisted language that will make
your brain into cottage cheese. :)
Parity says "However, if you can become proficient in MUSHcode, you can master -any-
programming language. I promise."
Moth says "Woo!"
CONNSWITCH-CMD:$connswitch *:@pemit %#=[switch(hasflag(*Scaramouche),0,no,1,yes)]
Parity peers at prospero, "That looks good, except you have 'scaramouche' hardcoded
into your command instead of using %0.
Moth says "Oh:)"
Parity says "So it will always tell you whether scaramouche is connected. :)"
Moth says "But that's what I wanted;)"
Parity says "Even if you do 'connswitch moth' ;)"
Moth says "Oh;)"
Moth lafs
Dunross says "Um, okay, try that?"
Moth likes to live in a fantasy world of my own creation!
ISCONNECTED-CMD:&isconnected *:@pemit %#=[switch(hasflag(*%0,0,is not connected,1,
is connected)]
Moth tries it again
Parity notes that Dunross is missing the closing-parentheses on hasflag().
Moth says "Okay, got it"
CONNSWITCH-CMD:$connswitch *:@pemit %#=[switch(hasflag(*Scaramouche),0,no,1,yes)]
Dunross hmms.
Parity nods to Moth, "Good!"
Dunross pokes moth.
Moth grins
HERE-CMD:&here *:@pemit %#=[switch(hasflag(*%0,0,is not connected,1,is connected))]
Moth had to scroll up and put it all together, but I get it...
Parity says "Dunross, change 'hasflag(*%0,' to 'hasflag(*%0),'"
Dunross okies?
Parity hmms?
Parity is looking at gondola/here-cmd and seeing a broken command. ;o
Parity says "Oh."
Moth offers Prospero a raisin.
Dunross says "Oh. wait."
Dunross says "Doh."
Parity says "Also, it should be '$here *' not '&here *'"
Dunross nods.
Owner: Dunross Key: *UNLOCKED* Pennies: 1
HERE-CMD:$here *:@pemit %#=[switch(hasflag(*%0),0,is not connected,1,is connected)]
Dunross noticed.
Dunross says "Okay, cool. I got nothing. laf. Better than getting Huh? :)"
Dunross keeps fixing this.
Parity hmmms.
Moth offers Prospero a raisin.
Parity says "Oh, you're missing the flag to check for."
Moth says "Like connected?"
Dunross says "ta da."
Parity says "Everybody should try, 'say hasflag(something)'"
Dunross says "Well, I couldn't figure out how that went."
Dunross noddles.
Moth gahs
Parity nods. ;)
Parity says "Now try, 'hasflag(something,connected)'"
Moth says "#-1 NOT FOUND"
Parity says "And finally, 'hasflag(moth,connected)'"
Moth says "#-1 NOT FOUND"
Moth says "1"
Moth says "So if I were on twice, it would say 2"
Parity says "The first error is saying you didn't give the right things to hasflag()."
Moth nods...
Moth says "So it's looking for a name or something and then the flag is the second argument"
Parity says "No, flags are either on or off."
Moth says "Oh okay"
Parity says "You will only ever get a 1 or a 0 or an error out of hasflag."
Moth nods
Dunross says "Hmm. laf. I'm trying to get it to put a name in there and it put a wrong
dbref for you, Moth."
Moth says "#528 #273 #386 #2 #252 #1098 #384"
Moth believes I'm 386
Moth is afraid to ex myself b/c of the major spam that would occurr
Dunross says "Yeah, but it tells me #2786 or something. :P"
Parity notes that it often writes commands with 'switch(<something>,<test-1>,<return-1>,
Moth says "Que?"
Moth says "Ohhhhh"
Moth says "No, I'm 386"
Parity says "Like, 'switch(hasflag(*%0,connected),0,no,1,yes,oops!)'"
Moth grins
Parity says "or in a real case of @Pemit %#=switch(<something>) I often make my default,
'Something has gone wrong! Please contact Parity about this problem.'"
Moth says "Suddenly that Harley motorcycle code makes sense;p"
Parity has defaults even in switches that should -never- be able to trigger the code.
Moth nods...
Dunross says "Oh wait. laf. It's telling me my own dbref. Hmm."
Dunross nods.

HERE-CMD:$here *:@pemit %#=[switch(hasflag(*%0,connected),0, #% is not connected,1,
%# is

Parity says "Ah, You're trying to be clever."
Dunross laughs.
Moth was keepin it simple;p
Dunross says "Apparently not. :P"
Parity says "You want to put '%0' in for the name, in this case."
Dunross nods, was about to try that next.
Moth ahhs, "I see.."
Parity will teach you how to be clever in a future class. :)
Moth will need it;p
Dunross says "Interesting. If it's a person without a dbref, it's confused. That's cause
we haven't a statement for non-existent people?"
Dunross grins.
Parity nods.
Moth says "Wow, you could muse over that for days..."
Parity says "You can make the conditional part of your switch '0,is connected,1,is not
connected,is not a player'"
Moth oooohs
Dunross says "And it knows the difference?"
Parity says "That would be a more robust solution."
Dunross nods.
Moth hmms
Dunross says "How does it know which one to pick, not connected or not a player?"
Parity says "Well, what -we- know is that if someone is not a player, 'hasflag
*some-arbitrary-string,connected)' will return '#-1 NOT FOUND'"
Dunross says "In your syntax?"
Dunross says "Ah."
Dunross says "That's part of hasflag"
Parity says "We could actually put '#-1 NOT FOUND' in as a condition, and have a
default of 'Oops!', but we don't expect 'Oops!' to ever be possible."
Parity says "So, it depends on how robust you want your code to be."
Dunross nods, sees how hasflag already knows how to take NOT FOUND vs simply not
Parity might well do, 'switch(hasflag(*%0),0,is not connected,1,is connected,#-1
NOT FOUND,is not a player,Oops -- Error!)'
Parity says "The 'Oops -- Error!' part should never happen, but if you make a little
change to your code and do it wrong, you might suddenly get 'Oops -- Error!' and then
you'll know you broke something."
Parity says "So, defaults that will 'never' be triggered are a good thing for debugging."
Dunross nods.
Dunross hmms.
Dunross says "Wow. I have so learned something today. cackle."
Parity grins.
Parity says "Okay. Is everyone ready to learn @switch now?"
Moth says "Oh sure"
Dunross says "Wait, one more question. :)"
Parity nods.
Parity notes that class looks to be running over 2 hours, and it will understand if
people need to go. "Yes, Dunross?"
Dunross says "So in your last example with the oops, in the paired if-then,
#-1 NOT FOUND,is not a player, the bit with the Oops -- is like an 'if' with no
'then' or was it like a second 'then' with the previous 'is not a player'?"
Parity uhms.
Parity says "If you think of switch as a chain of 'if-then-else' statements,"
Moth says "It's the else part of that"
Parity says "The default case is the final 'else'"
Moth says "like the Bigger than two"
Parity says "
Dunross ahs and noddles.
Dunross says "Okay, right, sorry. if-then-else."
Dunross says "So you can see each sequence after the first as a series of elses, in a way?"
Parity nods to Dunross, "Yes. switch() is very much like a chain of if-then-else. It
is actually possible to make switches where more than one thing matches, but there is
an implicit else in there.
Parity says "So only the first match will be 'true'."
Dunross nods.
Moth nods
Parity notes that in conditions '*' matches anything and '?' matches any single character.
"I don't want to go into that today, but remember it so you'll understand why a '*' or a
'?' in a condition has unexpected results."
Dunross nods.
Parity says "Okee. ;)0"
Parity says "Now, let's talk about the -other- switch, the command '@switch'."
Parity says "Try typing in, '@switch 0=0,zero,1,one'"
Parity says "err."
Parity says "Don't. :)"
Moth lafs
Dunross says "Heh."
Parity says "Try typing in, '@switch 0=0,say zero,1,say one'"
Dunross says "zero"
Parity says "And then, '@switch 1=0,say zero,1,say one'"
Moth says "zero"
Dunross says "one"
Moth says "one"
Parity says "Try typing in, '@switch something=0,say zero,1,say one,say unexpected value'"
Dunross says "unexpected value"
Moth says "unexpected value"
Dunross reads those statements again.
Dunross nods.
Parity nods, "You'll notice that, except for being a command, @switch behaves very much
like switch(). It's a series of if-then-elses, but instead of 'evaluating' to 'say zero'
it 'executes' the command 'say zero'.
Moth ahhhhs
Dunross says "That's important."
Dunross says "The distinction, that is."
Parity nods!
Parity says "Very."
Dunross says "So, which is better? Does one take up more mush-brain than the other?"
Parity says "You should use switch() instead of @switch when you can."
Dunross nods.
Parity says "switch() is better, for two reasons; it's more efficient, and it lets you
reuse more code."
Parity says "Let's re-implement our connected command with @switch."
Dunross nods.
Moth nods
Parity says "&newswitch-cmd myobj=$newswitch *:@switch hasflag(*%0,connected)=0,@pemit
%#=Not connected,1,@pemit %#=Connected,#-1 NOT FOUND,@pemit %#=Not a player,@pemit
Dunross says "Ack don't tell me yet! ;)"
Parity will give you an exercise soon, it promises. ;)
Parity says "Hopefully what I typed is something like what you were doing? Is it clear
to everyone?"
Moth nods
Moth needs syntax, trust me;p
Dunross nods, is still doing it, "Yes, I had started '@switch 0=0,is not connected'
Dunross says "But you still have to use hasflag()."
Parity says "Well, yes. :)"
Parity says "hasflag is the function that tells you if someone is connected."
Parity says "'@switch 0=0,is not connected' will -always- come back with 'is not
Parity says "Because '0' always evaluates to '0'."
Moth says "Like I did earlier with putting Scaramouche in the command?"
Parity says "Worse, you won't see anything, because it will try to executed 'is not
connected' as a command, and your -object- will see 'Huh?' ... but the person
invoking the command will see nothing."
Moth says "Oh..."
Parity says "So, in the @switch case we need an @pemit on -every- branch."
Dunross blahs, tries to get it on the gondola.
Parity says "In reality, we would never code this like this."
Dunross says "Yeah, I like switch() better for that example."
Parity says "You use @switch when you want to do very different things in each branch."
Parity is just trying to keep it simple and familiar.
Moth nods
Parity says "And, while I'm at it, to demonstrate why and when switch() is
preferable to @switch."
Moth can see why switch() is preferred
Moth says "Much less typing for starters"
Dunross says "Clearer relationships between the if-then-else."
Moth nods
Dunross nods, gets it to work.
Parity nods, "But you can do things in @switch that you simply cannot do in switch()."
Dunross says "Really?"
Parity nods.
Parity says "Type, 'help commands' ..."
Parity says "Err."
Parity says "try, 'help command list' rather. :)"
Help available for MUSH Commands:

drop enter examine get give goto
help inventory kill leave LOGOUT look
take throw use version whisper WHO
" : ; & # \\

@@ @chown @clone @create @decompile @destroy
@dig @doing @dolist @drain @edit @emit
@entrances @eval @femit @find @force @fpose
@fsay @halt @last @link @list @listmotd
@lock @mvattr @name @notify @oemit @open
@parent @password @pemit @program @ps @quitprog
@quota @robot @search @set @stats @sweep
@switch @teleport @trigger @unlink @unlock @verb
@wait @wipe

{ 'help commands2' for more }
Parity says "You can put -any- command into a switch."
Dunross says "And you can't in switch()"
Parity nods, "Switch only evaluates to a string... now, by putting functions into those
strings, we can do a lot...
but not everything.
Parity says "Let's work on an example."
Dunross will trust you. :)
Dunross nods.
Moth oooohs
Dunross says "ooh?"
Parity says "First we want a command 'play/*' that recognizes 'play/get' and 'play/drop'"
Parity says "Instead of doing -two- commands, we're going to do one."
Dunross nods.
Parity says "&play-cmd myobj=$play/*:@switch <...>"
Dunross says "This is so we don' thave to do separate attribute lines like with the
channel exercise?"
Parity asks you to fill in the <...> with a simple '@pemit #384=The flag is <...>'
Parity says "Err."
Parity asks you to fill in the <...> with a simple '@pemit %#=The flag is <...>' type
Parity nods, "One attribute will do everything. :)"
Moth okies
Parity says "At the same time that we're learning @switch, you can see that this is
the other way to implement +command/flag type things."

PLAY-CMD:$play/*:@switch @pemit %#=The flag is <...>
Parity says "Moth, don't literally put <...> in, but rather, make a switch that does
'@Pemit %#=The flag is drop' when %0 is 'drop', and 'The flag is get' when %0 is get,
and 'The flag is unrecognized' when the flag is anything else."
Moth says "oops..."
Moth believes I'm confused now
Moth says "So the switch bits...we're supposed to do as in the previous example...yes?"
Parity nods. ;)
Parity says "I think so."
Parity says "Your @switch should look a lot like the @switch we were playing with before."
Moth says "Okay"
PLAY-CMD:$play/*:@switch red= @pemit%#=The flag is red.,@switch blue=@pemit %#=The flag
is blue.,Error
Dunross hmms.
Moth says "We were using hasflag then...what are we using now?"
Parity says "Dunross, you're missing a space between 'pemit' and '%', and you have an
'=' instead of a ',' after red..."
Parity says "We're using '%0'"
Dunross nods.
Parity says "We start with, '@switch %0=drop,@pemit %#=The flag is drop'"
Moth says "Oh okay"
Parity says "And then have another case for 'get' and a default case for 'unrecognized'."
PLAY-CMD:$play/*:@switch %0=red, @pemit %#=The flag is red.,@switch %0=blue, @pemit
%#=The flag is blue.,Error
Parity says "Dunross, the syntax for @switch is, '@switch <test value>=<case 1>,
<action 1>,<case 2>,<action 2>,<default action>'"
Moth says "Is that more like it? Close?"
Parity says "so, you only need to have '@switch' appear once in your command."
PLAY-CMD:$play/*:@switch %0=drop,@pemit %#=The flag is 'drop',%0=get,@pemit
%#=The flag is 'get',The flag is unrecognized
Dunross ohs.
Dunross works on it.
Parity says "Almost, Moth. The 'Is <case> equal to <test value>' is implied by the
switch syntax, so the '%0=' doesn't belong before 'get'."
Moth says "Oh okay"
Parity says "Just the value that you're testing for goes in the 'test' slots."
PLAY-CMD:$play/*:@switch %0=red, @pemit %#=The flag is red.,blue,@pemit %#=The flag
is blue.,@pemit %#=Sorry, outta those.
Moth okies, the %0= is part of the @switch syntax... you set the condition and then
you add in however many variables you want? It could go on ad infinitum?
Database checkpoint in progress - stand by...
Database checkpoint complete.
Parity ahhhs.
Moth says "Am I close anyway?"
Parity says "Dunross, because the comma is significant to switch, if you're going to
include a comma in your commands, you need to mark it as special somehow. The easiest
way to do this is to put curly braces {} around your action sequence."
Dunross figured it out. ;)
Parity nods.
Dunross says "About 3 seconds ago. ;)"
PLAY-CMD:$play/*:@switch %0=red, @pemit %#=The flag is red.,blue,@pemit %#=The flag is
blue.,@pemit %#=What color was that?
Parity okays. :)
PLAY-CMD:$play/*:@switch %0=drop,@pemit %#=The flag is 'drop',get,@pemit %#=The flag
is 'get',The flag is unrecognized
Dunross chuckles.
Parity looks at prospero.
Moth tsks... you're much more clever than I am
Moth notes prospero is getting spammy;)
Moth offers Prospero a raisin.
Parity says "Moth, You forgot the '@pemit' on the default case."
Moth is lost then;p
Moth looks at it again
Parity says "Instead of 'The flag is unrecognized' after the last comma, you need to
say, '@pemit %#=The flag is unrecognized.'"
Parity says "The way you have it now, the MUSH will try to execute as a command, 'The
flag is unrecognized.' and your object will see a 'Huh?' but you won't see anything."

(Post-lecture note: This next one is right:)
PLAY-CMD:$play/*:@switch %0=red, @pemit %#=The flag is red.,blue,@pemit %#=The flag is
blue.,@pemit %#=What color was that?

Parity nods to Dunross, "Good!"
Dunross says "Ah, dankles. :)"
Moth says " about now?"
PLAY-CMD:$play/*:@switch %0=indigo,@pemit %#=The cat is 'indigo',mauve,@pemit %#=The
cat is 'mauve',@pemit %#=What cat?
Parity nods, "Good. :)"
Moth changes it to ferret
Moth offers Prospero a raisin.
Parity says "OKay, now, everyone '@create Ball' and 'give <myobj>=Ball'"
Dunross says "Oh, well, of course, I didn't do the get/drop commands. :P"
Dunross chuckles.
Moth changed mine;p
Parity says "You'll have to change it. ;)"
Dunross laughs.
Parity says "The next step in our exercise, is, instead of having an @pemit for the
'drop' and 'get' cases, put in the commands, 'drop ball' and 'get ball'"
Parity ehs.
Parity says "Oh, yes, you'll have to '@set <myobj>=inherit' to make that work for the
'get' case."
Moth okies
Parity isn't quite sure why. "Normally 'get' is not a privileged command, but MUSH has
a -huge- amount of options, which means all kinds of behaviour can change from one mush
to another even when they're the same version."
Moth says "So, the drop ball, get ball bits would go in the @switch
@switch %0=drop ball?"
Parity says "The part following the = on an @switch command is a series of 'pairs'
separated by commas. @switch %0=<test-value>,<commands>,<test-value>,<commands>,etc."
Moth nods
Parity says "If there's a last 'unpaired' element, that's the 'default' set of
Parity says "So, you want something more like, @switch %0=drop,drop ball"

(Post-lecture note: Dunross renames 'Gondola' to 'Bix')
PLAY-CMD:$play/*:@switch %0=get, @pemit %#=The flag is get.,drop,@pemit %#=The flag
is drop.,@pemit %#=What did I do?
PAINT-CMD:$paint/*:@switch %0=red, @pemit %#=The flag is red.,blue,@pemit %#=The flag
is blue.,@pemit %#=What color was that?

Moth says "And then the @pemit could be: The ferret drops the ball"
Parity says "there's no @pemit yet. :)"
Parity says "We'll do that next. :)"
Moth hmms
Parity says "Right now, we're replacing the '@pemit' command with a 'drop' or a
'get' command."
Moth thinks I'm lost again then. I thought we were just redoing that &play bits
by changing stuff
Parity nods.
Parity says "Change '@pemit %#=The ferret drops the ball' or whatever to 'drop
ball'. '@pemit' and 'drop' are both commands, so where one can go, the other can go."
Bix dropped Ball.
Moth says "So it would be... blahblahblah @switch %0=drop,drop ball,@pemit
%#=whatever,get,get ball,@pemit %#=whatever...?"
Ball has left.
Parity shakes his head.
Bix dropped Ball.
Parity says "No @pemit at all."
Moth says "Then I'm lost"
Dunross says "The action for play/get is now 'get ball'. No pemit at all.
just <case>,<action>."
Parity says "@switch %0=drop,drop ball is good... when we see 'drop' we do
the action 'drop ball'"
Parity says "But now, after the next comma, we get another test value."
Moth just blinks
Parity says "We don't want to test for '@pemit %#=whatever' we want to test for 'get'."
Ball has left.
Bix dropped Ball.
Moth says "Okay..."
PLAY-AGAIN-CMD:$play again/*:@switch %0=get,get ball,drop,drop ball,@pemit
%#=What was I supposed to do?
Parity nods to Dunross, "That's it. ;)
Parity says "Moth, exa Bix/play-again-cmd"
Dunross says "Oh good. Cause I'm having to make stuff up again. :P"
Parity tries to explain more clearly.
Moth has it
Moth was just trying to do too much at once
Parity says "Remember in 'switch()' we had 'switch(<test value>,<case1>,<return1>,
<case2>,<return2>)' ?"
Dunross nods.
Parity says "In @switch, we have, '@switch <test value>=<case1>,<action1>,<case2>,
Moth nods
Parity says "We have an '=' to set the first argument off from the others, and we
have 'actions' instead of 'return values', but otherwise the two are very similar."
Parity says "Make sense?"
PLAY-AGAIN-CMD:$play again/*:@switch %0=drop,drop ball,get,get ball,@pemit
%#=Come again?
Moth says " is it activated?"
Parity says "Look at the pattern."
Parity says "What would match '$play again/*' ?"
Moth typed 'play again' 'drop ball' and got a huh?
Moth says "That was my guess"
Dunross says "Right, but don't forget your two options. /get or /drop"
Parity says "'/' doesn't mean anything special."
Ball has left.
Prospero dropped Ball.
Dunross says "Hmm."
Parity says "To match '$play again/*:' We need to -literally- type the
non-special characters... 'play again/'. Only the '*' is special."
Ball has left.
Moth nods
Dunross says "Are we using the same ball?"
Parity says "Make sense now?"
Prospero dropped Ball.
Ball has left.
Parity says "Oh, dear."
Moth lafs
Parity says "Yes. ;)"
Bix dropped Ball.
Dunross nods. :P
Ball has left.
Parity should've had you name your toys differently.
Dunross says "Um. I set my ball inherit. ;P"
Moth says "Woo! Let's play hoops!"
Dunross nods, can rename that.
Parity chuckles, "You don't need your ball to be inherit, only your command-object."
Moth adds /dribbles ball;p
Dunross ahs. ;)
Parity says "OKay, one last thing."
Dunross says "Alright, who has my ball? :P"
Moth set mine inherit
Moth lafs... the ferret has them both!
Moth chuckles
Moth offers Prospero a raisin.
Moth says "Okay...last thing"
Prospero dropped Ball.
Prospero dropped Ball.
Ball has left.
Ball has left.
Moth says "Okay;p"
Parity says "Suppose you want to do what Moth tried to do before, and have -both-
the command 'drop ball' -and- the command '@emit The ferret drops the ball.'
happen when the command 'play/drop' is entered?"
Dunross nods.
Moth says "That's where I got hung up"
Parity says "In the place of -a- command in an @switch, we can put a -series- of
commands. To do this, we put curly braces around the commands, and separate the
commands with ';'."
Moth ohs
Dunross nods, has seen this.
Moth nods, has too
Parity says "So, instead of 'drop ball' we have 'drop ball ; @emit The ferret
drops the ball.'"
Parity says "Oops."
Moth hasn't set it, but has seen it
Parity says "So, instead of 'drop ball' we have '{ drop ball ; @emit The ferret
drops the ball. }'"
(Post-lecture note: Yes, in theory you can separate your commands with ';' and
-not- put them inside curly braces {}, but in most cases this won't work right.
The curly braces {} will add readability, so always use them, it'll make life easier.)
Parity invites you to modify your commands.
Parity says "Put an @emit, or an @pemit, or both, in with 'drop' and 'get'."
Dunross nods.
Dunross says "I think I screwed mine up when I renamed the ball."
Dunross tries to fix it.
PLAY-AGAIN-CMD:$play again/*:@switch %0=get,(get soccerball;@emit Bix grabs
the soccerball.),drop,(drop soccerball; @emit Bix drops the soccerball.),@pemit
%#=What was I supposed to do?
Parity says "Dunross, you need curly braces {} not parentheses ()."
Parity hopes you're not on a european keyboard.
Moth hmmms...
Parity says "Some older european keyboards didn't have angular brackets
<> and curly braces {}..."
Parity says "MUSH is -not- friendly to such keyboards."
Bix grabs the soccerball.
Bix drops the soccerball.

PLAY-CMD:$play/*:@switch %0={ drop ball ; @emit The ferret drops the ball and
waits for raisins.},{ get ball ; @emit The ferret gets the ball. Clever Prospero!},
{ tackle ball ; @emit The ferret tackles the ball. That's a personal foul, mister.},
@pemit %#=What ball?
Parity says "Moth, you've got your commands layed out nicely, but you lost the values
to test for."
Parity says "@switch <input>=<test>,<actions>,<test>,<actions>,<default actions>"
PLAY-AGAIN-CMD:$play again/*:@switch %0=get,{get soccerball;@emit Bix grabs the
soccerball.;@pemit Bix got it!},drop,{drop soccerball; @emit Bix drops the soccerball.;
@pemit Bix lost it.},@pemit %#=What was I supposed to do?
Parity nods to Dunross, "Good!"
Parity says "Err."
Moth looks at Dunross' again;p
Parity says "Except you probably want your @pemit to @pemit %#= ;)"
Dunross noddles, was fixing that. :)
Bix grabs the soccerball.
Dunross says "Yay."
Bix drops the soccerball.
Parity says "RIght now those @pemits are going into the void. Right now your object
is seeing a complaint that there is no such object, as, for example, 'Bix lost it.'"
PLAY-AGAIN-CMD:$play again/*:@switch %0=get,{get soccerball;@emit Bix grabs the
soccerball.;@pemit %#= Bix got it!},drop,{drop soccerball; @emit Bix drops the
soccerball.;@pemit %#= Bix lost it.},{@pemit %#=What was I supposed to do? @emit
Someone's confused about what to do with this ball.}
Dunross hmms.
Dunross says "I got the pemits now..."
Parity nods, "That's fixed correctly."
(Post-lecture note: Except I don't notice the missing ';' in the default case for
a couple more poses... )
Dunross ahs.
Dunross says "And you have to do emits before pemits?"
Parity was still speaking while you were fixing. ;)
Parity says "No."
Dunross nods.
Dunross says "A ;."
Parity says "You can mix the commands up in any order. The ';' separates them,
and they occur in the order written."
Dunross nods.
Parity says "This is one of those things that doesn't work when typed in the
way it works in code."
PLAY-AGAIN-CMD:$play again/*:@switch %0=get,{get soccerball;@emit Bix grabs
the soccerball.;@pemit %#= Bix got it!},drop,{drop soccerball; @emit Bix drops
the soccerball.;@pemit %#= Bix lost it.},{@pemit %#=What was I supposed to do?;
@emit Someone's confused about what to do with this ball.}
Parity ahs, "Yes, that was an important ';' to put in. ;)
Dunross snickers.
Dunross says "Moth is too quiet. :P"
PLAY-CMD:$play/*:@switch %0=drop,{ drop ball ; @emit The ferret drops the ball
and waits for raisins.},get,{ get ball ; @emit The ferret gets the ball. Clever
Prospero!},tackle,{ tackle ball ; @emit The ferret tackles the ball. That's
a personal foul, mister.},@pemit %#=What ball? How about more raisins...
Moth is working;p
Parity nods, and turns to study prospero.
Prospero dropped Ball.
The ferret drops the ball and waits for raisins.
Ball has left.
The ferret gets the ball. Clever Prospero!
Parity thinks that looks right.
Prospero dropped Ball.
The ferret drops the ball and waits for raisins.
The ferret tackles the ball. That's a personal foul, mister.
Dunross says "I am already going to have to hurt this ferret."
Ball has left.
The ferret gets the ball. Clever Prospero!
Parity chuckles. "I wouldn't... ferret's have sharp claws and teeth... :)"
Moth nods, sees what I did and gets it
Parity says "Okay! That looks like we're there. Any questions or clarifications needed?"
Moth says "Nope! Thanks for running the class over;)"
Moth is slow;)
Dunross says "Can we just review real quick? We're talking: commands, switch,
@switch, and hasflag. :)"
Parity nods.
Dunross says "Yes, thanks for everything! You were so patient, seriously."
Moth says "Summary syntax would be nice, actually:)"
Parity says "An attribute is set with, '&<attribute-name> <object-name>=<value>"
Parity says "A value like, '$<something>:<something>' is a command."
Parity says "'&my-cmd myobj=$mine:@pemit %#=It's all mine!' will create a command
'mine' on 'myobj' that will pemit 'It's all mine!' to the invoker."
Parity says "If you use '*' in the command format, any string will match the '*',
and you can get what the invoker typed with '%0' for the first *, %1 for the
second *, and so on, up to '%9' for the tenth *."
Parity says "'&my-cmd myobj=$mine *:@pemit #384=%0 is all mine!' will pemit,
for example, 'The ferret is all mine!' if you type 'mine ferret'"
Parity says "'&my-cmd myobj=$mine *:@pemit %#=%0 is all mine!' will pemit,
for example, 'The ferret is all mine!' if you type 'mine ferret'"
Parity says "switch() is a function; functions replace themselves with text
according to certain rules. switch() has special 'if-then-else' rules for
what it is replaced with."
Parity says "switch(1,1,one,0,zero,unexpected value) is replaced with 'one'."
Parity says "Functions are evaluated from the inside out, so you can put a
function inside of a function."
Parity says "switch(hasflag(me,connected),1,one,0,zero,unexpected value) is
replaced with 'one' if you're connected, 'zero' if you're not, and 'unexpected
value' if you're on a MUSH that doesn't know about the special word 'me' and
tries to find an object named 'me'."
Moth chuckles
Parity says "switch(hasflag(#1,connected),1,one,0,zero,unexpected value) is replaced
with 'one' if 'God' is connected, 'zero' if 'God' is not connected, and 'unexpected
value' only if something is really weird and #1 is not a player."
Parity says "@switch is like switch(), except that instead of replacing itself with
a value, it executes a set of commands."
Parity says "'@switch 1=1,say one,0,say zero,say unexpected value' makes the
executing object (You if you type in directly, the command-object if you put
it in a command) do the command 'say one'."
Parity says "'@switch hasflag(#1,connected)=0,@pemit %#=God is not connected,
1,@pemit %#=God is not connected,@pemit %#=What? God is not a player?' will
@pemit a different thing depending on whether 'hasflag()' (a function, which
should replace itself with some text) replaces itself with '1' '0' or some
error message."
Parity says "When writing an @switch, you can use %0 from a command argument
as your 'first argument/test argument' value."
Parity says "And you should put your commands inside of curly braces {}."
Dunross says "You type too fast, Parity. And I type fast. :P"
Parity says "'&switch-cmd myobj=$myswitch *:@switch %0=hi,@pemit #384=Well,
hi there!,bye,@pemit %#=Good-bye, then!,@pemit %#=What?' will create a command
that pemits 'Well, hi there!' if you do 'myswitch hi', 'Good-bye, then!' if you
do 'myswitch bye', and 'What?' if you do anything else. The curly braces mark
off your commands, so you can have commas that are not treated special as part
of the @switch, you can put a whole string of commands seperated by ';' inside
instead of one @pemit, etc."
Parity says "And, finally, you can get help with 'help command list' 'help
function list' 'help switch()' 'help @switch' and others. ;)"
Moth has to note for the record that you've been great, horrendously patient,
extremely courteous and folks need to take advantage of these classes... When
can we do this again?
Parity says "help hasflag() for instance. :)"
Parity expects to hold another class in two weeks.
Moth says "Woo!"
Moth will be there...
Dunross says "Most excellent."
Parity says "That seems like a good amount of time between classes. :)"
Parity says "Any more questions?"
Moth nods, allows brain cells to rejuvenate, hopefully
Parity grins.
Dunross says "Moth is right, Parity. I've been in environments for 10 years and that
was the most patient coder-lesson experience I've ever had."
Moth says "And if you can teach -me- to code, you can teach -anyone-... ;)"
Dunross says "Yeah. Moths are slow. ;)"
Parity has an ulterior motive.. if it can teach people to code, the will be more
code-wizards and it will be less overworked... :)
Moth chuckles
Dunross laughs, "No joke. That's how you do it."
Dunross says "Thanks a million. :)"
Moth says "Well, I will try.."
Parity says "No problem. :)"
Moth says "Thanks a mill..."
Parity has a question for all you now. :)
Prospero dropped Ball.
Houston, we have lift-off. The ferret launches the ball across the room.
Dunross says "Oh, God. Is that what you made today?"
Moth says "Oh sure"
Dunross says "Oh, certainment."
Parity says "Do you have any idea what you'd like to see addressed in the
next session?"
Moth is so new to coding, I wouldn't be able to tell you...
Moth says "I mean, I guess that's evident;p"
Parity grins.
Ball has left.
The ferret gets the ball. Clever Prospero!
Dunross says "Well, I like trying to understand the functions. I mean, we are
pretty functional...both Moth and I have built and done things, but again, it's
not efficient or taking advantage of things like switch()."
Parity says "Well, I expect it to be phrased as 'how to do X' not 'how to use the
such-n-such command' ;)"
Moth nods...
Moth needs to figure out how to build.... water... laf
Dunross says "I'd like to see stuff on how to set up a Master Room. laf. ;)
Functions on objects, globals, etc."
Moth says "Weather"
Dunross says "Oi. Weather."
Parity mmmmmms.
Moth says "We've got to figure that out tho..."
Dunross says "I like the exercise method you did Parity, adding each time."
Dunross says "And that means I can keep my object with the bits on it to review."
Moth nods
Parity says "Everything I've taught you can be applied to master room objects.
Perhaps we'll try to cover user-functions and other neat tricks next time."
Moth says "Hands on is critical"
Moth nods, cool
Prospero dribbles it up the middle like Julius Erving!
Parity nods, and agrees that hands on is critical.
Dunross nods, has figured out a master room in the backyard of his own place,
but that doesn't really mean much, save it manages to work.
Parity says "Okay, so you like cumulative exercises. What was the thing you
-least- liked in this lecture?"
Dunross says "Least?"
Parity nods.
Moth says "The fact that I was slow... ;)"
Parity can't improve if it doesn't know what it does wrong.
Parity says "And I don't believe I was perfect. :)"
Moth says "I think it was pretty straight-forward..."
Dunross says "Nothing really. I liked working on just a set of related commands.
I liked the exercises. I liked the steps you took and were patient. I thought it
was all well done. When it got slow, it was due to 1. us needing a few minutes
to sort it out, 2. you mistyped something, which happens, no big deal."
Moth says "Maybe give a couple of practical uses for the code bits..."
Moth says " can use this to do blah"
Parity nods thoughtfully.
Moth says "That's where I have trouble sometimes... figuring out what I'd do with it"
Dunross says "True, maybe then continue work on a project? Like you may have our small
items to practice syntax on, but then we're simultanously working on a larger project
and adding to it each week?"
Parity says "Yes... I think I did that with the 'mywho' from the first lecture, but
not so much in this lecture."
Dunross says "So I could keep Bix, but I also know that I'm trying to work on
Weather stuff at my own place and so maybe relating the two might assist?"
Parity will need to think of a project that uses the techniques. ;o
Moth nods
Moth thinks that having at least one practical application for a section of code
learned would be a great way to tie it all together
Moth says "That'd really be my only suggestion. I think the rest is great..."
Dunross nods. "Well, yer making your ferret, yes? You know how to do the basic
bits to code an animal."
Moth says "Right..."
Parity nods. "Well... truthfully... @switch isn't practical except in the largest
most complex applications, but when you need it, you need it. ;o"
Dunross says "Feed, pet, play."
Moth says "Right... is just saying some of the switch stuff might relate well to
other things I wouldn't think to use it for... b/c of my lack of experience"
Moth says "That's all..."
Parity often does, for example, '@switch hasflag(%#,wizard)=1,one set of actions,0,
another set of actions'
Dunrossnods on switch. "Actually, I have something that might be improved by @switch
my own place, but still, I'm glad we know it...the travelling metaphor, Moth."
Moth doesn't know how it might apply, if at all, to different things, like weather...
or the transportation code on Myriad. That's all.
Dunross nods at Parity, "Exactly."
Parity says "But only when I need a command named the same thing to behave very differently."
Moth nods
Dunross nods, "Yeah, our transport is more a string of emits and then a teleport."
Dunross says "Switch might be overkill. ;)"
Moth nods
Dunross says "But you get the idea. :)"
Moth says "Anyhoo...that'd be my suggestion..."
Parity says "Usually you can stick a 'switch(hasflag(%#,wizard), ... ' into the
text to add extra info for staff."
Parity will work on it. ;)
Dunross says "Thanks again, Parity. ;)"
Moth says "Otherwise, it's great as it is... I think you're doing a fabulous job..."
Moth says "Thanks muchly..."
Dunross says "How does the log stuff work? Does Sio put it up?"
Parity says "Thank you!"
Parity nods.
Dunross cools.
Parity says "The logs will be posted at"
Parity says "Under 'resources'"
Moth nods, cool
Dunross grabs Bix and runs. :)
Prospero dropped Ball.
Houston, we have lift-off. The ferret launches the ball across the room.
Dunross says "Till next time then. :)"
Moth grins
Parity says "Class dismissed! :)"
Dunross salutes. :)
Parity waves.
Ball has left.
The ferret gets the ball. Clever Prospero!
Dunross laughs.
Dunross goes home.
Dunross has left.