CSC/ECE 517 Fall 2009/wiki1a 11 f1,: Difference between revisions

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But it’s really not a big deal, because calling the initialise method after the class or as a decorator is really not a major drawback.
But it’s really not a big deal, because calling the initialise method after the class or as a decorator is really not a major drawback.
=== “self” ===
In Python, one needs to write ''self'' as the first parameter of a method definition (alike Perl). Furthermore, Python doesn’t  require the variable name to be self. In Ruby, ''self'' is automatically available in a similar fashion as in C++.
Additionally, the method call ''self.method'' can be shortened to ''method'', as ''self'' is the default receiver.
=== Ruby continuations vs Python Generators ===
The use of continuations seem rather limited, and hard to understand, but it’s there in Ruby, and not in Python.
Continuations are useful when it comes to ''usecases''. However, they can be replicated in Python 3.1 with passing variables into ''.next()'' .
Python has generators. You can fake them in Ruby by using '''blocks''', or use continuations. Python generators are easy and clean.

Revision as of 05:31, 5 September 2009

Ruby and Python are both scripting languages whose popularity has sky rocketed in recent years. Both languages are High-Level, Garbage-collected, and Dynamically-typed. Both provide an interactive shell, standard libraries, and persistence support. So, what are the differences?

Points of comparison:

  • Language Features
  • Web programming environments
  • Features exclusive to each
  • Advantages of each over statically typed languages
  • Projects environments suited to each

Language Features

Private methods and variables

To make methods and instance variables private in Python, one always needs to write __ in front of the name. In Ruby, instance variables are private by default. Methods defined after the method call private are private.

Functions and methods

In Ruby, there are no separate functions and methods; all of them are methods.

string = 'Hello world'
puts string.count('o'), string.length  # prints 2, 11

In Python, there are separate methods and functions as shown in the example below.

string = 'Hello world'
print string.count('o'), len(string)  # prints 2, 11 – why not string.len()?

Ruby has reference to class in class body

Ruby:

class MyClass
    initialize_magick()
end

Rubys variant is cleaner, as the magic stuff is done in the class definition, so you see that it’s being done when you look at the class.

Python:

class MyClass:
    pass
initialize_magick(MyClass)

But it’s really not a big deal, because calling the initialise method after the class or as a decorator is really not a major drawback.

“self”

In Python, one needs to write self as the first parameter of a method definition (alike Perl). Furthermore, Python doesn’t require the variable name to be self. In Ruby, self is automatically available in a similar fashion as in C++.

Additionally, the method call self.method can be shortened to method, as self is the default receiver.

Ruby continuations vs Python Generators

The use of continuations seem rather limited, and hard to understand, but it’s there in Ruby, and not in Python. Continuations are useful when it comes to usecases. However, they can be replicated in Python 3.1 with passing variables into .next() .

Python has generators. You can fake them in Ruby by using blocks, or use continuations. Python generators are easy and clean.