Clarified about copying an immutable dictionary #11877
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WhiteBlackGoose
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Oct 2, 2025
| ## Remarks | ||
| When you manipulate an immutable dictionary a copy of the original dictionary is made, manipulations applied and a new immutable dictionary is returned. | ||
| When you manipulate an immutable dictionary, a new one is returned with the appropriate changes, while the old one is not altered. |
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Alternatively, "a new instance"? Or even "a new instance if necessary"?
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Alternatively: using the old wording but with "minimal copy" instead of "copy". Or "minimal (optimized) copy"
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Summary
I think saying that a copy is made is misleading, because it makes the person assume a copy of the whole dictionary is made, whereas in reality operations like Add are O(log(N)) complex.