Implicit Conversions Do not define implicit conversions. Use the explicit keyword for conversion operators and single-argument constructors. Implicit conversions allow an object of one type (called the destination type is implicit, particularly if the list has only a single element. 15 Type conversion operators, and constructors that are callable with a single argu- ment, must be marked explicit in the class allow for additional flexibility in e.g., type composition. Copy/move constructors and assignment operators are usually easier to define correctly than alternatives like Clone(), CopyFrom() or Swap(), because

Global variables Nested/Local/Inner Classes and Functions List Comprehensions Default Iterators and Operators Generators Lambda Functions Conditional Expressions Default Argument Values Properties True/False xrange(5) if x != y for z in xrange(5) if y != z) Default Iterators and Operators link￿ Use default iterators and operators for types that support them, like lists, dic- tionaries, and files. Definition: dictionaries and lists, define default iterators and membership test operators (“in” and “not in”). Pros: The default iterators and operators are simple and efficient. They express the operation directly, without

line with the first character inside the parenthesis. Spacing 2 Place spaces around all binary operators (=, +, -, <-, etc.). Exception: Spaces around =’s are optional when passing parameters in a function