Enum Event

pub enum Event<'a> {
    Content(Content<'a>),
    Begin(Grouping),
    End,
    Visual(Visual),
    Script {
        ty: ScriptType,
        position: ScriptPosition,
    },
    Space {
        width: Option<Dimension>,
        height: Option<Dimension>,
    },
    StateChange(StateChange),
    EnvironmentFlow(EnvironmentFlow),
}

All events that can be produced by the parser.

For Renderer Implementors

When an Event is referreing to an “element”, it is referring to the next logical unit of content in the stream. This can be a single Event::Content element, a group marked by Event::Begin and Event::End, an Event::Visual or an Event::Script element, an Event::Space, or an Event::StateChange.

[Event::Alignment]s, and [Event::NewLine]s are not considered elements, and must never occur when an element is expected.

Examples

The following examples all constitute a single element:

Input: \text{Hello, world!}

[Event::Content(Content::Text("Hello, world!"))];

Input: x^2_{\text{max}}

[
    Event::Script {
        ty: ScriptType::SubSuperscript,
        position: ScriptPosition::Right,
    },
    Event::Begin(Grouping::Normal),
    Event::Content(Content::Text("max")),
    Event::End,
    Event::Content(Content::Ordinary {
        content: 'x',
        stretchy: false,
    }),
];

Variants

Content(Content<'a>)

The event is a Content element.

Begin(Grouping)

The events following this one constitute a “group” which counts as a single element (i.e., a set of elements within {} in LaTeX), until the Event::End event is reached.

End

Marks the end of a group initiated with Event::Begin.

Visual(Visual)

The n elements following this one constitute the content of the Visual element, where n is specified in the documentation of for each of the Visual variants.

Script

The n elements following this one constitute a base and its script(s), where n is specified in the documentation for each of the ScriptType variants.

Fields

ty: ScriptType

The type of the script.

position: ScriptPosition

The position of the script.

Space

This event specifes a custom spacing. This is produced by commands such as \kern, \hspace, etc.

If any of the components are None, then the spacing is set to 0 for that component.

Fields

width: Option<Dimension>

The amount of space to add before the element.

height: Option<Dimension>

The amount of space to add after the element.

StateChange(StateChange)

This event specifies a state change in the renderer.

This state change only applies to the current group nesting and deeper groups.

EnvironmentFlow(EnvironmentFlow)

This is a flow event that is emitted in mathematical environments such as align, cases, array, etc.

Trait Implementations

impl<'a> Clone for Event<'a>

fn clone(&self) -> Event<'a>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<'a> Debug for Event<'a>

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

Formats the value using the given formatter.

impl<'a> PartialEq for Event<'a>

fn eq(&self, other: &Event<'a>) -> bool

Tests for self and other values to be equal, and is used by ==.

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

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

impl<'a> StructuralPartialEq for Event<'a>