Python Mapping for Structures

A Slice structure maps to a Python class with the same name. For each Slice data member, the Python class contains a corresponding attribute. For example, here is our Employee structure once more:

struct Employee
    long number;
    string firstName;
    string lastName;

The Python mapping generates the following definition for this structure:

class Employee(object):
    def __init__(self, number=0, firstName='', lastName=''):
        self.number = number
        self.firstName = firstName
        self.lastName = lastName

    def __eq__(self, other):
        # ...

    def __ne__(self, other):
        # ...

    def __str__(self):
        # ...

    def __hash__(self):
        # ...
    # ...

The constructor initializes each of the attributes to a default value appropriate for its type:

Data Member TypeDefault Value
stringEmpty string
enumFirst enumerator in enumeration
structDefault-constructed value

You can also declare different default values for members of primitive and enumerated types.

The __eq__ method returns true if all members of two structures are (recursively) equal, and __ne__ returns true if any member differs.

The __str__ method returns a string representation of the structure.

For structures that are also legal dictionary key types, the mapping also generates relational operators (__lt____le____gt____ge__) and a __hash__ method. The __hash__ method returns a hash value for the structure based on the value of all its data members.

See Also