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Data-race freedom by construction

Category: Safety in languages · Status: stub · Lessons: chapter 02, Shared state

One line: A language rule that makes data races impossible to write in the first place — Rust's ownership with Send and Sync, or actors that never share memory.

How it connects

flowchart LR
  n_data_race["Data race"]
  n_data_race_freedom["Data-race freedom by construction"]
  n_send_and_sync["Send and Sync"]
  n_data_race_freedom -->|prevents| n_data_race
  n_data_race_freedom -->|uses| n_send_and_sync
  classDef center stroke-width:3px
  class n_data_race_freedom center
  classDef outside stroke-dasharray: 4 3
  class n_data_race,n_send_and_sync outside

In each language
Rust The Rustonomicon ↗: safe Rust guarantees an absence of data races, though not of race conditions
Go A convention, not a rule: Effective Go ↗ says share memory by communicating, so only one goroutine has access to a value at a time
JavaScript Web workers ↗ exchange messages whose data is copied rather than shared
Swift The Swift 6 language mode ↗ prevents data races at compile time
Erlang and Elixir All data in messages between processes is copied ↗, except refc binaries and literals

Where to read more