Macro is_contained_in 

macro_rules! is_contained_in {
    ([$($matcher:expr),* $(,)?]) => { ... };
    ($($matcher:expr),* $(,)?) => { ... };
}

Matches a JSON array where every element matches one of the provided matchers.

This macro succeeds if:

• the input is a JSON array
• every element in the array matches exactly one matcher
• matchers are not reused
• extra matchers may be provided and left unmatched
• order does not matter

This macro fails if:

• the input is not a JSON array
• any element in the array fails to match all matchers

Accepts both bracketed (json::is_contained_in!([ ... ])) and unbracketed (json::is_contained_in!(...)) forms.

Example:

let value = j!(["a", "b", "c"]);
assert_that!(
    value,
    json::is_contained_in![eq("a"), eq("b"), eq("c"), eq("d")]
);

How it works

• Each matcher can match at most one element
• Extra matchers may remain unused
• Every element in the array must be matched

Alias

This macro is re-exported as json::is_contained_in!.