added types section

This commit is contained in:
Leah Hanson 2013-07-02 18:00:32 -04:00
parent b1e305626e
commit 587e35062c

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@ -397,61 +397,46 @@ filter(x -> x > 5, [3, 4, 5, 6, 7]) #=> [6, 7]
[add_10(i) for i=[1, 2, 3]] #=> [11, 12, 13] [add_10(i) for i=[1, 2, 3]] #=> [11, 12, 13]
[add_10(i) for i in [1, 2, 3]] #=> [11, 12, 13] [add_10(i) for i in [1, 2, 3]] #=> [11, 12, 13]
####################################################
## 5. Types and Multiple-Dispatch
####################################################
# Type definition
type Tiger
taillength::Float64
coatcolor # no type annotation is implicitly Any
end
# default constructor is the properties in order
# so, Tiger(taillength,coatcolor)
# Type instantiation
tigger = Tiger(3.5,"orange") # the type doubles as the constructor function
# Abtract Types
abstract Cat # just a name and point in the type hierarchy
# types defined with the type keyword are concrete types; they can be instantiated
# types defined with the abstract keyword are abstract types; they can have subtypes
# each type has one supertype; a supertype can have zero or more subtypes.
type Lion <: Cat # Lion is a subtype of Cat
mane_color
roar::String
end
type Panther <: Cat # Panther is also a subtype of Cat
eye_color
Panther() = new("green") # Panthers will only have this constructor, and no default constructor.
end
#### ####
#### In progress point #### In progress point
#### ####
#################################################### #### Multiple Dispatch
## 5. Classes
####################################################
# We subclass from object to get a class.
class Human(object):
# A class attribute. It is shared by all instances of this class
species = "H. sapiens"
# Basic initializer
def __init__(self, name):
# Assign the argument to the instance's name attribute
self.name = name
# An instance method. All methods take self as the first argument
def say(self, msg):
return "%s: %s" % (self.name, msg)
# A class method is shared among all instances
# They are called with the calling class as the first argument
@classmethod
def get_species(cls):
return cls.species
# A static method is called without a class or instance reference
@staticmethod
def grunt():
return "*grunt*"
# Instantiate a class
i = Human(name="Ian")
print i.say("hi") # prints out "Ian: hi"
j = Human("Joel")
print j.say("hello") #prints out "Joel: hello"
# Call our class method
i.get_species() #=> "H. sapiens"
# Change the shared attribute
Human.species = "H. neanderthalensis"
i.get_species() #=> "H. neanderthalensis"
j.get_species() #=> "H. neanderthalensis"
# Call the static method
Human.grunt() #=> "*grunt*"
```
## Further Reading ## Further Reading
#### Link to Maunual
Still up for more? Try [Learn Python The Hard Way](http://learnpythonthehardway.org/book/) Still up for more? Try [Learn Python The Hard Way](http://learnpythonthehardway.org/book/)