Macro into_bset 

macro_rules! into_bset {
    (
    $( $key : expr ),* $( , )?
  ) => { ... };
}

Creates a BTreeSet from a list of elements.

The into_bset macro allows for convenient creation of a BTreeSet with initial elements. Elements passed to the macro are automatically converted into the set’s element type using .into(), facilitating the use of literals or values of different, but convertible types.

Note: The into_bset macro relies on the .into() method to convert each element into the target type of the BTreeSet. This means that the elements must be compatible with the Into<T> trait for the type T used in the BTreeSet. Also, this means that sometimes you must specify the type of collection’s items.

Origin

This collection is reexported from alloc.

Syntax

The macro can be called with a comma-separated list of elements. A trailing comma is optional.

// BTreeSet of &str
let set1 : BTreeSet< &str > = into_bset!( "a", "b", "c" );

// BTreeSet of String
let set2 : BTreeSet< String > = into_bset!{ "a".to_string(), "b", "c" };

// With trailing comma
let set3 : BTreeSet< i32 > = into_bset!( 1, 2, 3, );

Parameters

• $( $key:expr ),* $( , )?: A comma-separated list of elements to insert into the BTreeSet. Each element can be of any type that implements the Into<T> trait, where T is the type stored in the BTreeSet.

Returns

Returns a BTreeSet containing all the specified elements. The capacity of the set is automatically determined based on the number of elements provided.

Example

Basic usage with string slices:

let set  : BTreeSet< &str > = into_bset!( "one", "two", "three" );
assert!( set.contains( "one" ) );
assert!( set.contains( "two" ) );
assert!( set.contains( "three" ) );
assert_eq!( set.len(), 3 );

Example

Using with different types that implement Into<T>:

let numbers : BTreeSet< i32 > = into_bset!( 1, 2, 3 );
assert!( numbers.contains( &1 ) );
assert!( numbers.contains( &2 ) );
assert!( numbers.contains( &3 ) );

Example

Creating a BTreeSet of String from string literals:

let s : BTreeSet< String > = into_bset!{ "value" };
assert!( s.contains( "value" ) );