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

    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

# Help

## Keyboard Shortcuts

?
  Show this help dialog
S
  Focus the search field
⇤
  Move up in search results
⇥
  Move down in search results
⏎
  Go to active search result
+
  Collapse/expand all sections

## Search Tricks

Prefix searches with a type followed by a colon (e.g. `fn:`) to restrict the search to a given type.

Accepted types are: `fn`, `mod`, `struct`, `enum`, `trait`, `type`, `macro`, and `const`.

Search functions by type signature (e.g. `vec -> usize` or `* -> vec`)