#4822·book

Documentation issue in Section 19.3

Author: William-B-GCreated Aug 31, 2026Updated Aug 31, 2026
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Description of the problem: Possible wording error in Section 19.3 — “Parts of a Value with a Nested _

In Section 19.3, under “Parts of a Value with a Nested _, the text says:

“In all other cases (if either setting_value or new_setting_value is None) expressed by the _ pattern in the second arm, we want to allow new_setting_value to become setting_value.”

However, the assignment being discussed is:

rust
setting_value = new_setting_value;

Since new_setting_value is assigned to setting_value, it appears the wording should instead be:

“…we want to allow setting_value to become new_setting_value.”

I believe the current wording reverses the direction of the assignment. Could you please verify?

Suggested fix: I believe the last part of the passage should be '... setting_value to become new_setting_value.'