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gh-111307: Update design FAQ 'switch' entry (#115899)

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Terry Jan Reedy 2024-03-13 01:30:39 -04:00 committed by GitHub
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Doc/faq/design.rst
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@ -259,9 +259,11 @@ is evaluated in all cases.
Why isn't there a switch or case statement in Python?
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You can do this easily enough with a sequence of ``if... elif... elif... else``.
For literal values, or constants within a namespace, you can also use a
``match ... case`` statement.
In general, structured switch statements execute one block of code
when an expression has a particular value or set of values.
Since Python 3.10 one can easily match literal values, or constants
within a namespace, with a ``match ... case`` statement.
An older alternative is a sequence of ``if... elif... elif... else``.
For cases where you need to choose from a very large number of possibilities,
you can create a dictionary mapping case values to functions to call. For
@ -290,6 +292,9 @@ It's suggested that you use a prefix for the method names, such as ``visit_`` in
this example. Without such a prefix, if values are coming from an untrusted
source, an attacker would be able to call any method on your object.
Imitating switch with fallthrough, as with C's switch-case-default,
is possible, much harder, and less needed.
Can't you emulate threads in the interpreter instead of relying on an OS-specific thread implementation?
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