12 Immutability questions from the Functional Programming bank, written for Indian campus drives and tech interviews. Every question has a verified answer and an AI-tutor explanation on placd.
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A.deferring duplication of shared data until a modification is requested, then copying only what is changed
B.the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs
C.an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything
D.a collection that preserves all previous versions of itself whenever it is updated
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2. Which term means: "a collection that preserves all previous versions of itself whenever it is updated"?
Senior
A.Structural sharing
B.Persistent data structure
C.Copy-on-write
D.Why avoid mutation
Answer + AI explanation with Pro
3. Which statement is correct?
Senior
A.Persistent data structure — an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything
B.Persistent data structure — deferring duplication of shared data until a modification is requested, then copying only what is changed
C.Persistent data structure — a collection that preserves all previous versions of itself whenever it is updated
D.Persistent data structure — the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs
Answer + AI explanation with Pro
4. What is Structural sharing?
Senior
A.the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs
B.deferring duplication of shared data until a modification is requested, then copying only what is changed
C.an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything
D.a collection that preserves all previous versions of itself whenever it is updated
Answer + AI explanation with Pro
5. Which term means: "an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything"?
Senior
A.Why avoid mutation
B.Structural sharing
C.Persistent data structure
D.Copy-on-write
Answer + AI explanation with Pro
6. Which statement is correct?
Senior
A.Structural sharing — deferring duplication of shared data until a modification is requested, then copying only what is changed
B.Structural sharing — an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything
C.Structural sharing — the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs
D.Structural sharing — a collection that preserves all previous versions of itself whenever it is updated
Answer + AI explanation with Pro
7. What is Copy-on-write?
Mid
A.a collection that preserves all previous versions of itself whenever it is updated
B.deferring duplication of shared data until a modification is requested, then copying only what is changed
C.an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything
D.the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs
Answer + AI explanation with Pro
8. Which term means: "deferring duplication of shared data until a modification is requested, then copying only what is changed"?
Mid
A.Copy-on-write
B.Why avoid mutation
C.Persistent data structure
D.Structural sharing
Answer + AI explanation with Pro
9. Which statement is correct?
Mid
A.Copy-on-write — the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs
B.Copy-on-write — a collection that preserves all previous versions of itself whenever it is updated
C.Copy-on-write — an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything
D.Copy-on-write — deferring duplication of shared data until a modification is requested, then copying only what is changed
Answer + AI explanation with Pro
10. What is Why avoid mutation?
Junior
A.deferring duplication of shared data until a modification is requested, then copying only what is changed
B.a collection that preserves all previous versions of itself whenever it is updated
C.an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything
D.the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs
Answer + AI explanation with Pro
11. Which term means: "the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs"?
Junior
A.Why avoid mutation
B.Copy-on-write
C.Structural sharing
D.Persistent data structure
Answer + AI explanation with Pro
12. Which statement is correct?
Junior
A.Why avoid mutation — the rationale that not changing values in place removes a major source of hidden coupling and hard-to-trace bugs
B.Why avoid mutation — an efficiency technique where an updated immutable collection reuses unchanged parts of the original instead of copying everything
C.Why avoid mutation — a collection that preserves all previous versions of itself whenever it is updated
D.Why avoid mutation — deferring duplication of shared data until a modification is requested, then copying only what is changed
Answer + AI explanation with Pro
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