Struct libdata::column::Tags

pub struct Tags(_);

Tags of a single entity.

This represents a set of tags. However, the set contains at most one value of each type. This is well suited for things like the header information about flows, for example.

This data storage is cummulative ‒ it is not possible to remove tags (only to replace them).

Methods

impl Tags

fn new() -> Self

Creates a new tag storage.

fn insert<V: Into<Value>>(&mut self, value: V) -> Option<Value>

Inserts a value into the set.

If a value of that column type is already present, the old one is replaced and returned.

fn contains(&self, ident: &Ident) -> bool

Checks if a tag of the given type is present.

fn get(&self, ident: &Ident) -> Option<&Value>

Returns the tag value.

This looks up the value of the given type, if any is present.

fn extend(&mut self, other: Self)

Consumes other and inserts all its content into self.

If both self and other contain value of the same type, the one in self is overwritten and other wins.

Params

• other: The other tag storage to incorporate into self.

fn len(&self) -> usize

Returns how many tags there are inside.

fn is_empty(&self) -> bool

Checks if the storage is empty.

fn idents(&self) -> Keys<Ident, Value>

Iterates over the identities in the tags.

Trait Implementations

impl Clone for Tags

fn clone(&self) -> Tags

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Tags

fn fmt(&self, __arg_0: &mut Formatter) -> Result

Formats the value using the given formatter.

impl Default for Tags

fn default() -> Tags

Returns the "default value" for a type.

impl Eq for Tags

impl PartialEq for Tags

fn eq(&self, __arg_0: &Tags) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, __arg_0: &Tags) -> bool

This method tests for !=.