Struct Metadata 

pub(crate) struct Metadata {
    pub(crate) max_bytes_needed: usize,
    pub(crate) guaranteed_utf8: bool,
}

Available on crate feature formatting only.

Metadata about a format description.

Fields

max_bytes_needed: usize

The maximum number of bytes needed for the provided format description.

The number of bytes written should never exceed this value, but it may be less. This is used to pre-allocate a buffer of the appropriate size for formatting.

guaranteed_utf8: bool

Whether the output of the provided format description is guaranteed to be valid UTF-8.

This is used to determine whether the output can be soundly converted to a String without checking for UTF-8 validity.

Trait Implementations

impl Add for Metadata

type Output = Metadata

The resulting type after applying the + operator.

fn add(self, rhs: Self) -> Self::Output

Performs the + operation.

impl Debug for Metadata

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Metadata

fn default() -> Self

Returns the “default value” for a type.

impl Sum for Metadata

fn sum<I>(iter: I) -> Self

where I: Iterator<Item = Self>,

Takes an iterator and generates Self from the elements by “summing up” the items.