Helium

laika.helium.Helium

See theHelium companion object

class Helium

Configuration API for the Helium theme settings.

Helium can be fully configured with its Scala API and does not require any configuration files.

The entry point for all configuration steps is always Helium.defaults to ensure there are sensible defaults in place for all the options you omit in your configuration.

For each configuration step you need to choose one of the four selectors, either all to specify options for all three output formats or site, epub or pdf to select a single format. Not all options are available for all formats, but the IDE's context help and the documentation below can guide you.

In the minimal example below we only specify some metadata for all formats as well as the navigation depth for EPUB and PDF:

val theme = Helium.defaults
.all.metadata(
title = Some("Project Name"),
language = Some("de"),
)
.epub.navigationDepth(4)
.pdf.navigationDepth(4)
.build

Laika also provides convenient constructors for some of the data types used frequently in its theme API. You can import laika.theme.Color._ for specifying colors with hex("ffaaff") or rgb(255, 0, 0) and laika.ast.LengthUnit._ for specifying sizes with px(12) or pt(9) or other available units.

The final call to build produces a ThemeProvider that can be passed to Laika's transformers or the laikaTheme sbt setting:

Example for sbt plugin:

laikaTheme := theme

Example for the library API:

val transformer = Transformer
 .from(Markdown)
 .to(EPUB)
 .parallel[IO]
 .withTheme(theme)
 .build

Attributes

Companion: object
Source: Helium.scala
Graph
Supertypes: class Object

trait Matchable

class Any
Self type: Helium

Members list

Type members

Classlikes

Selects the configuration options available for all three output formats.

This means that it only contains the options that exist in all three formats, for anything specific to one or two formats you need to use their respective selectors.

Attributes

Source: Helium.scala
Supertypes: class Object

trait Matchable

class Any
Self type: all.type

Selects the configuration options available for EPUB generation.

Attributes

Source: Helium.scala
Supertypes: class Object

trait Matchable

class Any
Self type: epub.type

Selects the configuration options available for PDF generation.

Attributes

Source: Helium.scala
Supertypes: class Object

trait Matchable

class Any
Self type: pdf.type

Selects the configuration options available for site generation.

Attributes

Source: Helium.scala
Supertypes: class Object

trait Matchable

class Any
Self type: site.type

Value members

Concrete methods

Builds a theme provider that can be passed to the sbt plugin's laikaTheme setting or the withTheme method of parsers and transformers when using the library API.

Attributes

Source: Helium.scala

Creates a new Helium configuration using this instance as a base and the provided theme as the extension.

The exact mechanics of extending a theme vary depending on the type of functionality supported by themes. They are roughly as follows:

- For functionality that is an accumulation of features, for example input files, parser extensions, renderer overrides or AST rewrite rules, the effect is accumulative, this theme and the extensions will be merged to a single set of features.

- For functionality that is provided by unique instances, for example the template engine or the default template, the effect is replacement, where the instance in the extension replaces the corresponding instance in the base, if present.

Attributes

Source: Helium.scala

Creates a new Helium configuration by applying provided extension, using this instance as a base.

In contrast to the extendWith overload, this method can be used when an extension does not only provide additional resources and/or extension bundles, but also simply needs to talk to the Helium configuration API, e.g. to configure how/when CSS/JS resources are to be included.

The functionality of this method is essentially a superset of the extendWith overload, as the provided handler can internally call the other method, too.

Attributes

Source: Helium.scala

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