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borrow checker

The part of the compiler that enforces the borrowing rules.

The borrow checker verifies that references never conflict (many shared or one mutable) and never outlive their referents.

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Examples

  • let first = &v[0]; v.push(4); println!("{first}"); is rejected with E0502: push needs v mutably while first still borrows it.

See also

reference mutable reference lifetime
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