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Last edited: GB June 14, 1983 6:47 PM

LOOPS Course Summary

Accessing Objects and Variables

($ name) evaluates to the object or class named name.

($! atom)evaluates to the object or class whose name is the value of atom
(@ accessExpr)evaluates to the value of the instance variable, class variable, or property of these
referred to by accessExpr in self.
(@ obj accessExpr)evaluates to the value of the instance variable, class variable, or property of these
referred to by accessExpr in obj
(←@ accessExpr newValue)sets the value of the variable accessed by accessExpr in self to newValue
(←@ obj accessExpr newValue)sets the value of the variable accessed by accessExpr in obj to newValue
accessExpr is the concatenation of any combination of the following with evaluation strictly left to right
:ivNameinstance variable ivName
::cvNameclass variable cvName
:,propNamevalue of property propName
.selectorvalue returned by sending the unary message selector
N.B.a ! (bang) after any of the puctuation in the four lines above will cause the atom following it to be evaluated
and that value to be used as the name. Within an accessExpr a lisp variable is prefixed with a backslash "\"
(i.e. ::fee.fie:!\foe:,fum will get the value of CV fee of self and send it the message fie, then it will get the instance
variable whose name is the value of the lisp variable foe from the object returned by the message fie, then it
will get the value of property fum of that IV)

Defining and Editing Classes

(DC className supersList)(← ($ Class) New className supersList)create a class with name className and
supers supersList
(EC className)(← ($ className) Edit)edit the class definition of class className

Defining and Editing Methods

(DM className selector)creates a function with the name className.selector to be used by the method
called by selector and puts you in the editor
(DM className selector fnName)causes the function with the name fnName to be used by the method called
by selector
(EM className selector)edit the method used by selector in class className

Creating, Editing, and Inspecting Instances

(← class New)creates a new instance of class
(← class New ’name)creates a new instance of class with the name name
(← obj Edit)(EI obj)edit obj

(← obj Inspect)(INSPECT obj)create an inspect window for obj

(←New class selector arg1 ... argN)create a new instance of class and sends it the the message selector with
arguments arg1 ... argN

Sending Messages

(← obj selector arg1 ... argN)send obj the message selector with arguments arg1 ... argN
(←Super obj selector arg1 ... argN)in method selector invokes super method for that selector with arguments
arg1 ... argN
(←SuperFringe obj selector arg1 ... argN)invokes all the immediate super methods of obj for that selector with the
arguments arg1 ... argN
(←! obj expr arg1 ... argN)send obj the message whose selector is the value of expr with the
arguments arg1 ... argN

Active Values

#(localState getFn putFn)localState is where the value is stored (this may be another active value)
getFn is the function called on read access and putFn is called on write access

the value returned by getFn in the value of the get operation and putFn has
responsibility for changing the value of localState using the function PutLocalState



Debugging

(BreakIt obj varName)break whenever the instance variable varName of obj is
accessed
(UnBreakIt obj varName)remove the break on variable varName of obj
(BreakMethod className selector)break whenever the method selector is used by any
instance of class className
(TraceMethod className selector)trace whenever the method selector is used by any
instance of class className
(UNBREAK onlyMostRecentFlg)standard Lisp function to unbreak or untrace methods
(BreakIt obj varName propName type breakOnGetAlsoFlg)break whenever the variable varName of obj is accessed
(TraceIt obj varName propName type breakOnGetAlsoFlg)trace whenever the variable varName of obj is accessed
(UnBreakIt obj varName propName type)remove the break on variable varName of obj
To attach a gauge and monitor a variable:
(←New ($ gaugeType) Attach obj ivName selector)attaches a gauge of type gaugeType to the instance
variable ivName of obj

Rules

↑F gets you into the Rule Executive
(OK gets you out of it and UE puts you in the User Executive (where OK will get you back again))
Variables are accesed by using the access expressions as defined above
accessExprgets value of variable (do not use @)
accessExpr←newValuevariable accessed gets newValue
\lispVarNamefor referring to lisp variables use backslash
.selector sends unary message to self
(unary message is one that requires no arguments besides self)
(DefRSM className selector)creates a new rule set for the class className invoked by selector and
places you in the rule editor

(← ruleSet CopyRules ’newRuleSetName)copies the ruleset ruleSet into a new one called newRuleSetName
(← ruleSet ER)ER(ruleSet)edit ruleSet

(ListRuleSets className)generates a listing of all the rule sets defined for the class className

Browsers

(Browse classList)creates a browser window for the class lattice structure of the classes in classList and their
descendants
left or middle button in title area of the browser window updates the lattice structure
Left Mouse Buttongets pop-up menu to print information about class structure and methods
Middle Mouse Buttongets pop-up menu to aid in generating new classes or methods

An asterisk at the end of the name of any item in the menu signifies that there are multiple options for this item
To use the default option, click the left button, for a menu of options click the middle button (i.e. EM* will get a menu with EM and EM!)
To copy from class to class use the left button to "BoxNode" of recepient class then with the middle button menu select the "Move" item with the middle button to get a menu for either copying of moving of IVs, CVs, Methods, or RuleSets
"Specialize" on the middle button menu will create a new subclass of the one selected and ask for a name in the prompt window
"DefineMethod" on the middle button menu will create a new method for that class and prompt for its selector

Saving and Restoring Files

(FILES?)Lisp will ask you to assign a filename to each entity it does not already have a file name for
Type yes to specify the file names. For each entity type the filename to save it or ] to not
have it saved
LineFeed (LF) means the same as the previous entity
(MAKEFILE filename)saves the file on the file server on the directory currently connected
(LOAD filename)loads the file from the file server on the directory currently connected