1.12

Implicitly Shared Custom Type

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Objective: Copy-on-write pattern in value objects, implicit sharing

Comment: Qt contains about 100 implicit shared class and value types with intensive data should be implemented with this pattern. QSharedData and QSharedDataPointer are the key classes here. The assignments could contain even QExplicitlySharedDataPointer to indicate the case that complexity does not increase much. The idea of simple reference counting should become clear.

Beginner

• What is Copy-on-write pattern?

Intermediate

• What is Implicitly Shared Custom Type?
• How does Implicitly Shared Custom Type work?
• How does Qt value type memory management work?
• What is QSharedData (reference counting)?
• What is QSharedDataPointer?
• What is the difference between implicit and explicit sharing?

Expert

• When to use implicit/explicit sharing?

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Course material content

Copy-on-Write pattern

Implicitly Shared Custom Type

Qt Value Type memory management

QSharedData

QSharedDataPointer

Implicit vs Explicit sharing

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Exhaustive reference material mentioned in this topic

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