Struct ArgAttrs 

pub struct ArgAttrs<'a> { /* private fields */ }

A borrowed Nix attribute set value.

Obtained from PrimOpArg::as_attrs or PrimOpValue::as_attrs. Provides read access to the attribute set without owning any GC references itself.

Implementations

impl<'a> ArgAttrs<'a>

pub fn get(&self, key: &str) -> Result<PrimOpValue<'a>>

Get an attribute by name.

Returns an owned PrimOpValue that holds a GC reference to the attribute’s value. The caller is responsible for the GC reference; PrimOpValue releases it on drop. The value carries the same callback-frame lifetime as this attribute-set wrapper.

Errors

Returns Error::KeyNotFound if the key does not exist.

pub fn has(&self, key: &str) -> Result<bool>

Check if an attribute exists.

Errors

Returns an error if the lookup itself fails (not if the key is absent).

pub fn keys(&self) -> Result<Vec<String>>

Return all attribute keys in this set.

Errors

Returns an error if iteration fails.

pub fn len(&self) -> usize

Return the number of attributes in this set.

pub fn is_empty(&self) -> bool

Return true if the attribute set is empty.