item_02_PEP8Style.py

# Item 2: Follow the PEP 8 style guide


# Whitespace: In Python, whitespace is syntactically significant. Python
# programmers are especially sensitive to the effects of whitespace on
# code clarity.

# 1. Use spaces instead of tabs for indentation.
# 2. Use four spaces for each level of syntactically significant indenting.
# 3. Lines should be 79 characters in length or less.
# 4. Continuations of long expressions onto additional lines should be
#     indented by four extra spaces from their normal indentation level.
# 5. In a file, functions and classes should be separated by two blank lines.
# 6. In a class, methods should be separated by one blank line.
# 7. Don't put spaces around list indexes, function calls, or keyword
#     argument assignments.
# 8. Put one-and only one-space before and after variable assignments.


# Naming: PEP 8 suggests unique styles of naming for different part in the
# language.

# 1. Functions, variables, and attributs should be in lovercase_underscore
#     format.
# 2. Protected instance attributes should be in _leading_underscore format.
# 3. Private instance attributes should be in __double_leading_underscore
#     format.
# 4. Classes and exceptions should be in CapitalizedWord format.
# 5. Module-level constants should be in ALL_CAPS format.
# 6. Instance methods in classes should use self as the name of the first
#     parameter (which refers to the object).
# 7. Class methods should use cls as the name of the first parameter (which
# refers to the class).


# Expressions and Statements: The Zen of Python states: "There should be one-
# and preferably only one-obvious way to do it."

# 1. Use inline negation (if a is not b) instead of negative of positive
#     expressions (if not a is b)
# 2. Don't check for empty value (like [] or '') by checking the length
#     (if len(somelist) == 0). Use if not somelist and assume empty values
#     implicitly evaluate to False.
# 3. The same thing goes for non-empty values (like [1] or 'hi'). The statement
#     if somelist is implicitly True for non-empty values.
# 4. Avoid single-line if statements, for and while loops, and except compound
#     statements. Spread these over multiple lines for clarity.
# 5. Always put import statements as the top of a file.
# 6. Always use absolute names for modules when importing them, not names
#     relative to the current module's own path. For example, to import the foo
#     module for the bar package, you should do from bar import foo, not just
#     import foo.
# 7. If you must do relative imports, use the explicit syntax from . import foo.
# 8. Imports should be in sections in the following order: standard library
#     modules, third-party modules, your own modules. Each subsection should
#     have imports in alphabetical order.


# Things to Remember

# 1. Always follow the PEP 8 style guide when writing Python code.
# 2. Sharing a common style with the larger Python community facilitates
#     collaboration with others.
# 3. Using a consistent style makes it easier to modify your own code later.