r[type.inferred]
r[type.inferred.syntax]
Syntax
InferredType :_
r[type.inferred.intro] The inferred type asks the compiler to infer the type if possible based on the surrounding information available.
r[type.inferred.constraint] It cannot be used in item signatures.
It is often used in generic arguments:
let x: Vec<_> = (0..10).collect();