How to lookup a value in HashMap with a composite key containing a String without allocating

· Users Rust Lang · Sept. 2, 2026, 1:24 p.m.
Summary
This blog post discusses an advanced technique for looking up a value in a HashMap using a composite key that includes a String without causing additional memory allocation. It explores how to utilize the Equivalent trait with the hashbrown API and addresses the need for borrowing with the standard library's HashMap API, ultimately suggesting the use of a common type to streamline the process.
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