Enum tfm::ligkern::lang::PostLigOperation

pub enum PostLigOperation {
    RetainBothMoveNowhere,
    RetainBothMoveToInserted,
    RetainBothMoveToRight,
    RetainRightMoveToInserted,
    RetainRightMoveToRight,
    RetainLeftMoveNowhere,
    RetainLeftMoveToInserted,
    RetainNeitherMoveToInserted,
}

A post-lig operation to perform after performing a ligature operation (Operation::Ligature).

A lig operation starts with a pair of characters (x,y) and a “cursor” on x. The operation then inserts another character to get, say, (x,z,y). At this point the cursor is still on x. The post-lig operation does two things:

1. First, it potentially deletes x or y or both.
2. Second, it potentially moves the cursor forward.

After this, if the cursor is not at the end of the list of characters, the lig-kern program is run for the new pair starting at the cursor.

For example, the post-lig operation PostLigOperation::RetainLeftMoveNowhere retains x and deletes y, leaving (x,z). It then moves the cursor nowhere, leaving it on x. As a result, the lig kern program for the pair (x,z) will run.

On the other hand, if the post-lig operation PostLigOperation::RetainLeftMoveToInserted runs, y is still deleted but the cursor moves to z. This is the last character in this list and there no more pairs of characters to consider. The lig/kern program thus terminates.

In general all of the post-lig operations are of the form RetainXMoveY where X specifies the characters to retain and Y specifies where the cursor should move.

Variants

RetainBothMoveNowhere

Corresponds to the /LIG/ property list element.

RetainBothMoveToInserted

Corresponds to the /LIG/> property list element.

RetainBothMoveToRight

Corresponds to the /LIG/>> property list element.

RetainRightMoveToInserted

Corresponds to the LIG/ property list element.

RetainRightMoveToRight

Corresponds to the LIG/> property list element.

RetainLeftMoveNowhere

Corresponds to the /LIG property list element.

RetainLeftMoveToInserted

Corresponds to the /LIG> property list element.

RetainNeitherMoveToInserted

Corresponds to the LIG property list element.

Trait Implementations

impl<'arbitrary> Arbitrary<'arbitrary> for PostLigOperation

fn arbitrary(u: &mut Unstructured<'arbitrary>) -> Result<Self>

Generate an arbitrary value of Self from the given unstructured data.

fn arbitrary_take_rest(u: Unstructured<'arbitrary>) -> Result<Self>

Generate an arbitrary value of Self from the entirety of the given unstructured data.

fn size_hint(depth: usize) -> (usize, Option<usize>)

Get a size hint for how many bytes out of an Unstructured this type needs to construct itself.

impl Clone for PostLigOperation

fn clone(&self) -> PostLigOperation

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for PostLigOperation

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

Formats the value using the given formatter.

impl PartialEq<PostLigOperation> for PostLigOperation

fn eq(&self, other: &PostLigOperation) -> bool

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

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for PostLigOperation

impl Eq for PostLigOperation

impl StructuralEq for PostLigOperation

impl StructuralPartialEq for PostLigOperation