You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: spacing.rs
    path of file: ./repos/intellij-rust/src/test/resources/org/rust/ide/formatter/fixtures
    
    the code of the file until where you have to start completion: extern    crate    std    as    ruststd   ;

use   core    ::    hash  ::   {    self    ,    Hash    }    ;
use core ::intrinsi
    
    fn    from_iter    <   I    :    IntoIterator    <   Item     =    T   >   >   (   iter   :    I   )   ->    Vec  <  T >  {
        let mut iterator = iter.into_iter();
        let mut vector =    match    iterator . next ()     {
            None=>return      Vec::new()    ,
            Some    (   element   )    =>     {
                let(   lower    ,      _   )    =     iterator.size_hint();
                // ...
            }
        };
        // ...
    }