Macro metadata 

macro_rules! metadata {
    ($key:expr, $value:expr) => { ... };
}

👎Deprecated since 0.5.0: Use group! instead

Creates a key-value metadata pair for structured error context.

This macro creates an ErrorContext::metadata entry.

Deprecated

Use group! instead since version 0.5.0.

Arguments

• $key - The metadata key
• $value - The metadata value