Messages
Type-safe communication between actors.
What is a Message?
Messages are the only way actors communicate. Each message type defines what data it carries and what type of response it expects:
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Message Requirements
Messages must satisfy these trait bounds:
| Trait | Why |
|---|---|
Send | Messages may cross thread boundaries |
'static | Messages must outlive the send operation |
Result: Send | Response also crosses thread boundaries |
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Sending Messages
Cineyma provides three patterns for sending messages:
1. Request-Response (send)
Wait for and receive the response:
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2. Fire-and-Forget with Backpressure (do_send)
Send without waiting for response, but respect mailbox limits:
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3. Non-blocking Send (try_send)
Send immediately or fail if mailbox is full:
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Method Comparison
| Method | Waits for Response | Blocks on Full | Use Case |
|---|---|---|---|
send() | Yes | Yes | Need the result |
do_send() | No | Yes | Fire-and-forget, reliable |
try_send() | No | No | Non-blocking, lossy OK |
Built-in Messages
Cineyma provides some special messages:
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Message Design Patterns
Command Pattern
Messages that request an action:
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Query Pattern
Messages that request data:
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Event Pattern
Notifications that don't need responses:
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Error Handling
Handle send errors properly:
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