Module session 

Market session awareness — trading hours, holidays, status transitions.

Responsibility

Classify a UTC timestamp into a market trading status for a given session (equity, crypto, forex). Enables downstream filtering of ticks by session.

Guarantees

• Pure functions: SessionAwareness::status() is deterministic and stateless
• Non-panicking: all operations return Result or TradingStatus
• DST-aware: US equity hours correctly switch between EST (UTC-5) and EDT (UTC-4) on the second Sunday of March and first Sunday of November

Structs

SessionAwareness

Determines trading status for a market session.

Enums

MarketSession

Broad category of market session.

TradingStatus

Trading status at a point in time.

Functions

is_tradeable

Convenience: check if a session is currently tradeable.

is_us_market_holiday

Returns true if date (in ET) is a US equity market holiday (NYSE/NASDAQ closure).

trading_day_count

Count of US equity trading days (non-holiday weekdays) in the UTC millisecond range [start_ms, end_ms).