Treatment chain
std/flow::chain
Generics
◻ T (any)
Inputs
⇥ first: Stream<T>
⇥ second: Stream<T>
Outputs
↦ chained: Stream<T>
Chain two streams.
graph LR
     T("chain()")
     A["🟨 🟨 🟨 🟨 🟨 🟨"] -->|first| T
     B["… 🟪 🟪 🟪"] -->|second| T
     
     T -->|chained| O["… 🟪 🟪 🟪 🟨 🟨 🟨 🟨 🟨 🟨"]
     style A fill:#ffff,stroke:#ffff
     style B fill:#ffff,stroke:#ffff
     style O fill:#ffff,stroke:#ffff