Version 4 (modified by hopscc, 17 years ago) |
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Class Definitions
Classes are declared using the class keyword followed by the classname.
The class may have any of the usual access modifiers.
The Superclass inheritance and Interface conformance are indicated with the inherits and implements keywords.
Class Grammar
class <className> [is <AccessModifiers>] [has <Attributes>] [inherits <BaseClassName> ] [implements <InterfaceName> [, <InterfaceName>]...] [<DocString>] [ [<Variables>] [<Properties>] [<Methods> [<ClassEnums>] [<Sigs>] [<Invariants>] [<Tests>] [<SharedClause>] ]...
Interfaces
Interfaces are declared in much the same way except the keyword is interface and method and property bodies are not defined.
Interface hierarchies (SuperInterfaces) can also be specified using inherits
Interface Grammar
interface <InterfaceName> [is <AccessModifiers>] [has <Attributes>] [inherits <BaseInterfaceName> [, <BaseInterfaceName>]... ] [<DocString>] [ [<Properties>] [<Methods> [<ClassEnums>] [<Sigs>] [<Invariants>] [<SharedClause>] ]...
Instance and Class Variables
Instance and Class variables are declared within the class using keyword var.
Instance and Class variable definition Grammar
var <variableName> [as <Type>] [is <AccessModifiers>] [<DocString>] var _<variableName> [as <Type>] = <initialValue> [is <AccessModifiers>] [has <Attributes>] [<DocString>]
e.g.
var x as String var _y as int var _ya as int = 47 var z as int is private var t as int = 99 is protected, shared """ Temporary backup value """
If the name is prefixed with an _ its accessType defaults to protected and it is directly accessable from within the class method code.
Without that prefix on the name the variables accessType is public (by default) and
it must be accessed from within method code by prefixing the name with either self. or just ..
In either case the default accessModifier setting can be adjusted with an accessModifier clause. All Class and Instance variable names must start with a lowerCase Letter
Class (or static) variables are specified with the access Modifier shared as in is shared e.g.
var _x = 100 def tryx( opnd as int) as int return _x + opnd var y is protected # default public def tryy( opnd as int) as int return .y + opnd var statX as int = 45 is shared def x print .statX
Properties
++TBDone
Properties Grammar
++TBDone
Methods
Methods are defined using the keyword def
Method Grammar
++TBDone
The initializer or constructor method of a class is a special method called init which is implicitly called when a class instance is constructed. Its responsible for setting the contents of a class instance to an initial state. It doesnt return any value and is not inherited (i.e baseclass initialization must be done with an explicit call to a baseclass constructor).
If an init method is not specified the compiler runtime generates a noArg constructor that does nothing.
Constructor chaining can be done to another constructor in the same class (usually with a different number or Type of args) or to a Superclass constructor (using base.init) - this call must be the first executable line in the init method.
++accessing baseclass methods
Example
#Interfaces interface Audible def makesNoise as String interface Mateable pro mateName as String interface Breedable inherits Mateable pro childName as String # class declaration - note indentation class Bovidae def diet as String return 'Herbivorous Cud Chewing' def nHooves as String return 'four' class Sheep is public, nonvirtual # public is default anyway inherits Bovidae # Superclass implements Audible, Breedable var _lifeSpan as int = 8 is shared # years average # or var lifeSpan as int private shared var _age as int =1 var liveWeight as int is private var _isAlive as bool #shared #_lifespan = 8 def init _age = 1 .liveWeight = 2 _isAlive = true def makesNoise as String return 'Baaaaa' pro mateName as String get return 'Ram' set pass pro childName as String get return 'lamb' set pass def age( byNYears as int) _age += byNYears if _age > _lifeSpan _isAlive = false def gainWgt( wgt as int) .liveWeight += wgt def toString as String is new return 'Sheep:age=[_age], wgt=[.liveWeight], living=[_isAlive]' def main is shared s = Sheep() print 's=[s.toString]' s.age(1)