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 Type | Default Value |
|---|---|
string | Empty string |
enum | First enumerator in enumeration |
struct | Default-constructed value |
| Numeric | Zero |
bool | False |
sequence | None |
dictionary | None |
class/interface | None |
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.