Add RandomStream for independent, thread-friendly random sequences - #198
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Random previously drove every call through one shared, non-thread-safe mt19937 engine. RandomStream is an instantiable RNG that owns its own engine, so each subsystem/thread can get an independently seeded, reproducible sequence. Random is now a thin static wrapper around one shared RandomStream, so the distribution logic lives in a single place. Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
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Summary
Random's API was previously backed by a single shared, non-thread-safemt19937engine — concurrent calls from multiple threads are a data race.Fling::RandomStream: an instantiable RNG that owns its own engine, so a subsystem, job, or thread can get an independently seeded, reproducible sequence instead of sharing global state.Randomis now a thin static wrapper around one sharedRandomStream(s_Stream), so the distribution logic lives in a single place instead of being duplicated between the two.RandomStream::Init(...)was renamed toRandomStream::Reseed(...)to better describe re-seeding an already-constructed stream.Test plan
python3 scripts/check_comment_style.pycmake --build build --target FlingTests --parallel./build/FlingTests/bin/FlingTests— all 18 test cases pass (13389 assertions), including newRandomStreamcoverage: default construction, seed reproducibility, seed divergence,Reseed, independence between instances, and range checks for all generator methods.🤖 Generated with Claude Code