Struct KatexContext 

pub struct KatexContext {
    pub functions: KeyMap<String, Arc<FunctionSpec>>,
    pub html_group_builders: KeyMap<NodeType, HtmlBuilder>,
    pub mathml_group_builders: KeyMap<NodeType, MathMLBuilder>,
    pub symbols: Symbols,
    pub environments: KeyMap<String, Arc<EnvSpec>>,
    pub font_metrics: FontMetricsData,
}

Global context struct for KaTeX

The KatexContext serves as the central registry for all KaTeX functionality, containing mappings for functions, HTML/MathML builders, symbols, and environments. This design enables runtime extensibility of LaTeX commands without recompilation.

Fields

functions: KeyMap<String, Arc<FunctionSpec>>

Corresponds to _functions in defineFunction.js All registered functions Parser requires this dictionary

html_group_builders: KeyMap<NodeType, HtmlBuilder>

Corresponds to _htmlGroupBuilders in defineFunction.js All HTML builders. Should be only used in the define* and the build*ML functions.

mathml_group_builders: KeyMap<NodeType, MathMLBuilder>

Corresponds to _mathmlGroupBuilders in defineFunction.js All MathML builders. Should be only used in the define* and the build*ML functions.

symbols: Symbols

Corresponds to symbols in symbols.js Main symbol table mapping modes to character information

environments: KeyMap<String, Arc<EnvSpec>>

Corresponds to _environments in defineEnvironment.js All registered environments.

font_metrics: FontMetricsData

Font metrics data for character measurements

Implementations

impl KatexContext

pub fn make_glue<T>( &self, measurement: &Measurement<T>, options: &Options, ) -> Result<DomSpan, ParseError>

where T: AsRef<str>,

Create a glue (spacing) node with proper unit conversion

This method creates a spacing element that matches KaTeX’s behavior, properly converting measurements to CSS ems using the context’s calculate_size method.

impl KatexContext

pub fn define_function(&mut self, spec: FunctionDefSpec<'_>)

Set default values of functions

pub fn define_function_builders( &mut self, node_type: NodeType, html_builder: Option<HtmlBuilder>, mathml_builder: Option<MathMLBuilder>, )

Register only the HTML and MathML builders for a function

pub fn define_environment(&mut self, spec: EnvDefSpec)

Set default values of environments

pub fn get_global_metrics(&self, size: f64) -> &FontMetrics

Get the font metrics for a given size.

pub fn set_font_metrics(&mut self, font_name: &str, metrics: MetricMap)

Set or override font metrics for a specific font family

impl KatexContext

pub fn calculate_size<T>( &self, size: &Measurement<T>, options: &Options, ) -> Result<f64, ParseError>

where T: AsRef<str>,

Convert a Measurement (e.g., { number: 1.2, unit: "cm" }) into CSS ems for the given Options. Mirrors the logic in KaTeX calculateSize.

Returns an error if the unit is invalid.

Trait Implementations

impl Default for KatexContext

fn default() -> Self

Returns the “default value” for a type.