# 1.0.0[−][src]Function core::mem::size_of_val

    pub fn size_of_val<T: ?Sized>(val: &T) -> usize

Returns the size of the pointed-to value in bytes.

This is usually the same as `size_of::<T>()`. However, when `T` has no statically-known size, e.g., a slice `[T]` or a trait object, then `size_of_val` can be used to get the dynamically-known size.

# Examples

    use std::mem;

    assert_eq!(4, mem::size_of_val(&5i32));

    let x: [u8; 13] = [0; 13];
    let y: &[u8] = &x;
    assert_eq!(13, mem::size_of_val(y));Run