菜单
Explain how to build custom data structures in Cairo using structs, traits, and dictionaries; use when a request involves implementing mutable collections (like a vector) or handling Destruct/Drop with Felt252Dict.
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基于 SOC 职业分类
| name | cairo-custom-data-structures |
| description | Explain how to build custom data structures in Cairo using structs, traits, and dictionaries; use when a request involves implementing mutable collections (like a vector) or handling Destruct/Drop with Felt252Dict. |
Guide users through building mutable data structures on top of dictionaries and traits, including proper destruction.
references/custom-data-structures.md before answering.Felt252Dict for mutable storage.Destruct implementations for structs containing dictionaries.Felt252Dict and track len separately when emulating vectors.Nullable when storing generic T in a dict.Destruct to squash() dictionaries.Document Cairo language quirks, gotchas, and idiomatic workarounds; use when encountering unexpected compilation errors or behaviors in Cairo that differ from Rust.
Guide implementing custom numeric types in Cairo with invariant enforcement, overflow safety, and standard trait implementations; use when implementing fixed-point, signed integers, or other numeric primitives.
Explain how to write and run Cairo tests, including `#[test]`, assert macros, `#[should_panic]`, `#[ignore]`, and `#[available_gas]`; use when a request involves writing or running unit tests in Cairo.
Explain Cairo Array usage, ArrayTrait methods, array! macro, Span, and array read/write constraints; use when a request involves creating, updating, reading, or passing arrays in Cairo.
Explain Cairo associated items (functions, types, constants, implementations) in traits and impls; use when a request involves associated types, constants, or clarifying trait item placement in Cairo.
Explain Cairo closures, syntax, capture rules, type inference, and Fn traits; use when a request involves anonymous functions or passing behavior as a parameter in Cairo.