class is a system to declare a structure of data. actually, class is a model with some fields.
for example, we want to declare a model from Car. we can declare a class:
class Car
$name
$color
endclass
in above example, we declared a class named Car with name and color properties.
let’s use this:
class Car
$name
$color
endclass
$my_car = Car()
println($my_car)
output:
[PashmakObject name="Car"]
now, we want to set the properties:
class Car
$name
$color
endclass
$my_car = Car()
$my_car->name = 'BMW'
$my_car->color = 'white'
println($my_car->name + ' ' + $my_car->color)
output:
BMW white
so, let’s review the classes. for declaring the classes, we have to use class and endclass commands:
class TheClassName
# declare the properties
endclass
between them, you have to declare properties like normal variables:
class TheClassName
# declare the properties
$prop1
$prop2
$prop3; $prop4
endclass
default value for that properties is null(None).
also you can set the default value:
class TheClassName
# declare the properties
$prop1 = 'the default value'
$prop2 = 12
$prop3; $prop4
endclass
now, we declared our class, how to create a instance from that? actually, we can create infinitivly object from that. for example we have a thing named Car, this is a class and we have much many objects with Car class.
class TheClassName
# declare the properties
$prop1 = 'the default value'
$prop2 = 12
$prop3; $prop4
endclass
$my_object = TheClassName()
now, we can create object from a class. how to access to the properties? look at this example:
class Car
$name = 'default name'
$color
endclass
$my_car = Car()
println($my_car->name) # output: default name
we can access to the object properties by writing $varname->property_name
the -> symbol is important.
also you can set the value with this syntax:
class Car
$name = 'default name'
$color
endclass
$my_car = Car()
println($my_car->name) # output: default name
# setting the new value
$my_car->name = 'new name'
println($my_car->name) # output: new name
()+-/*%=}{<>[],. chars(literal chars)you can declare classes inside the namespaces like variables and functions.
for example:
namespace Models
class Car
$name
$color
endclass
endns
$my_car = Models.Car()
all of laws for classes in namespaces is like functions and variables.
you can use more features of the properties. actually, you can create any structure in your properties.
look at this example:
class Brand
$title = 'the brand name'
endclass
class Car
$name
$color
# the brand property is a object from Brand class
$brand = Brand()
endclass
$my_car = Car()
$my_car->name = 'my car'
$my_car->brand->title = 'BMW'
println($my_car->name)
println($my_car->brand->title)
output:
my car
BMW
actually, your property value can be a object from other property and this process can be continued recursivly.
you can access to properties by -> symbol:
# access to `prop3` of `prop2` of `prop1` of $obj
$obj->prop1->prop2->prop3
also you can set new properties on a object:
class Car
$name
$color
endclass
$my_car = Car()
$my_car->name = 'my car'
$my_car->color = 'red'
$my_car->the_new_prop = 'the value'
println($my_car->the_new_prop)
output:
the value
in the above example, property the_new_prop is not declared in class by default, but you can add props without any problem in objects.
also you can use Consts in classes.
for example:
class Person
$name = 'parsa'
$_age = 100 # age is const
endclass
$p = Person()
$p->_age = 50
output:
ClassConstError:...
if you want to set a peoperty as constant, you have to put a _ in the start of that name.
you can declare function inside classes. the class’s function is named Method.
look at this example:
class Cat
$name
func mio
println('miooo...')
endfunc
endclass
# create a object from Cat
$my_cat = Cat()
$my_cat->mio()
output:
miooo...
actually, you can call functions of a class.
another example:
class Cat
$name
func mio
println('miooo... my name is ' + $this->name)
endfunc
endclass
# create a object from Cat
$my_cat = Cat()
$my_cat->name = 'gerdoo'
$my_cat->mio()
output:
miooo... my name is gerdoo
in above example, we used a variable named $this. this variable is a pointer to self of object.
another example:
class Person
$name
func set_name($name)
$this->name = $name
endfunc
func say_hi()
println('hello. my name is ' + $this->name)
endfunc
endclass
$p = Person()
$p->set_name('parsa')
$p->say_hi()
output:
hello. my name is parsa
You can set object self properties by using $this variable like above examples
total syntax:
$object->method_name('arguments...', 'arg2...')
also all of classes extends parent methods.
for example:
class Father
func hi
# returnns this string
return 'hello world'
endfunc
endclass
class Child < Father; endclass
$obj = Child()
println($obj->hi())
output:
hello world