Macro macro_metadata_option

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

macro_metadata_option Macro

Extracts an option value from metadata.

Usage

use std::collections::HashMap;
use rss_gen::macro_metadata_option;

let mut metadata = HashMap::new();
metadata.insert("key", "value");
let value = macro_metadata_option!(metadata, "key");
println!("{}", value);

Arguments

• $metadata - A mutable variable that represents the metadata (of type HashMap<String, String> or any other type that supports the get and cloned methods).
• $key - A string literal that represents the key to search for in the metadata.

Behaviour

The macro_metadata_option macro is used to extract an option value from metadata. It takes a mutable variable representing the metadata and a string literal representing the key as arguments, and uses the get method of the metadata to find an option value with the specified key.

If the key exists in the metadata, the macro clones the value and returns it. If the key does not exist, it returns the default value for the type of the metadata values.

The macro is typically used in contexts where metadata is stored in a data structure that supports the get and cloned methods, such as a HashMap<String, String>.

Example

use std::collections::HashMap;
use rss_gen::macro_metadata_option;

let mut metadata = HashMap::new();
metadata.insert("key".to_string(), "value".to_string());
let value = macro_metadata_option!(metadata, "key");
assert_eq!(value, "value");