Struct Item

pub(crate) struct Item<'a, K: Keyword> {
    kwd: K,
    kwd_str: &'a str,
    args: &'a str,
    split_args: RefCell<Option<Vec<&'a str>>>,
    object: Option<Object<'a>>,
}

A single part of a directory object.

Each Item – called an “entry” in dir-spec.txt – has a keyword, a (possibly empty) set of arguments, and an optional object.

This is a zero-copy implementation that points to slices within a containing string.

Fields

kwd: K

The keyword that determines the type of this item.

kwd_str: &'a str

A reference to the actual string that defines the keyword for this item.

args: &'a str

Reference to the arguments that appear in the same line after the keyword. Does not include the terminating newline or the space that separates the keyword for its arguments.

split_args: RefCell<Option<Vec<&'a str>>>

The arguments, split by whitespace. This vector is constructed as needed, using interior mutability.

object: Option<Object<'a>>

If present, a base-64-encoded object that appeared at the end of this item.

Implementations

impl<'a, K: Keyword> Item<'a, K>

pub(crate) fn kwd(&self) -> K

Return the parsed keyword part of this item.

pub(crate) fn kwd_str(&self) -> &'a str

Return the keyword part of this item, as a string.

pub(crate) fn has_kwd_in(&self, ks: &[K]) -> bool

Return true if the keyword for this item is in ‘ks’.

pub(crate) fn args_as_str(&self) -> &'a str

Return the arguments of this item, as a single string.

fn args_as_vec(&self) -> Ref<'_, Vec<&'a str>>

Return the arguments of this item as a vector.

pub(crate) fn args(&self) -> impl Iterator<Item = &'a str>

Return an iterator over the arguments of this item.

pub(crate) fn arg(&self, idx: usize) -> Option<&'a str>

Return the nth argument of this item, if there is one.

pub(crate) fn required_arg(&self, idx: usize) -> Result<&'a str>

Return the nth argument of this item, or an error if it isn’t there.

pub(crate) fn parse_optional_arg<V: FromStr>( &self, idx: usize, ) -> Result<Option<V>>

where Error: From<V::Err>,

Try to parse the nth argument (if it exists) into some type that supports FromStr.

Returns Ok(None) if the argument doesn’t exist.

pub(crate) fn parse_arg<V: FromStr>(&self, idx: usize) -> Result<V>

where Error: From<V::Err>,

Try to parse the nth argument (if it exists) into some type that supports FromStr.

Return an error if the argument doesn’t exist.

pub(crate) fn n_args(&self) -> usize

Return the number of arguments for this Item

pub(crate) fn has_obj(&self) -> bool

Return true iff this Item has an associated object.

pub(crate) fn obj_tag(&self) -> Option<&'a str>

Return the tag of this item’s associated object, if it has one.

pub(crate) fn obj_raw(&self) -> Result<Option<(&'a str, Vec<u8>)>>

Try to decode the base64 contents of this Item’s associated object.

On success, return the object’s tag and decoded contents.

pub(crate) fn obj(&self, want_tag: &str) -> Result<Vec<u8>>

Try to decode the base64 contents of this Item’s associated object, and make sure that its tag matches ‘want_tag’.

pub(crate) fn parse_obj<V: FromBytes>(&self, want_tag: &str) -> Result<V>

Try to decode the base64 contents of this item’s associated object as a given type that implements FromBytes.

pub(crate) fn pos(&self) -> Pos

Return the position of this item.

This position won’t be useful unless it is later contextualized with the containing string.

pub(crate) fn offset_in(&self, s: &str) -> Option<usize>

Return the position of this Item in a string.

Returns None if this item doesn’t actually belong to the string.

pub(crate) fn arg_pos(&self, n: usize) -> Pos

Return the position of the n’th argument of this item.

If this item does not have a n’th argument, return the position of the end of the final argument.

fn last_arg_end_pos(&self) -> Pos

Return the position at the end of the last argument. (This will point to a newline.)

pub(crate) fn end_pos(&self) -> Pos

Return the position of the end of this object. (This will point to a newline.)

pub(crate) fn offset_after(&self, s: &str) -> Option<usize>

If this item occurs within s, return the byte offset immediately after the end of this item.

Trait Implementations

impl<'a, K: Clone + Keyword> Clone for Item<'a, K>

fn clone(&self) -> Item<'a, K>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a, K: Debug + Keyword> Debug for Item<'a, K>

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

Formats the value using the given formatter.