Collections & Strings

Collections and strings are Rust’s owned, borrowed, growable, and iterable building blocks for runtime-sized data.

Concepts

• Vec
• String and str
• HashMap
• BTreeMap and BTreeSet
• VecDeque
• Capacity and Reallocation
• Set Collections with HashSet and BTreeSet
• BinaryHeap Priority Queues
• The Slice Type

Patterns

• Borrowing Strings and Slices
• The Entry API
• Iterating Collections
• Choosing Collection Types
• Sorting and Binary Search on Slices

Antipatterns

• String Byte Indexing
• Holding Collection Element References Across Mutation
• Stale Slice Indices

Adjacent Notes

Ownership · Borrowing · Dynamically Sized Types · Index Panics vs get · Needless Clone · Unnecessary Collect · Copy and Clone

Sources

• The Rust Programming Language, ch. 8 “Common Collections” — the-book, https://doc.rust-lang.org/book/ch08-00-common-collections.html
• Standard library collections overview — std, https://doc.rust-lang.org/std/collections/index.html
• Standard library string module overview — std, https://doc.rust-lang.org/std/string/index.html