A Sass compiler that uses Dart Sass as an embedded child process.

The Dart Sass compiler is bundled with this package for macOS and Ubuntu 64-bit Linux. For other platforms you need to supply this separately, see the readme.

Some debug logging is available via a swift-log Logger that produces goodpath protocol and compiler lifecycle tracing at Logger.Level.debug log level, approx 300 bytes per compile request, and protocol and lifecycle error reporting at Logger.Level.debug log level for conditions that are also reported through errors thrown from some API.

You must shut down the compiler using shutdownGracefully(...) before the last reference to the object is released otherwise the program will exit.

Custom importer resolution

Dart Sass uses a different algorithm to LibSass for processing imports. Each stylesheet is associated with the importer that loaded it – this may be an internal or hidden filesystem importer. Import resolution then goes:

• Consult the stylesheet’s associated importer.
• Consult every DartSass.ImportResolver given to the compiler, first the global list then the per-compilation list, in order within each list.

The syntax used for a stylesheet.

How the Sass compiler should format the CSS it produces.

The kind of source map to generate for the stylesheet, returned in CompilerResults.sourceMap.

The format used for CompilerError.description and CompilerMessage.description.

A control over warnings and debug messages produced by the compiler

A Deprecation refers to a specific feature of the Sass compiler that is deprecated or planned to become deprecated.

By default, using a deprecated feature causes a warning – that is, a CompilerMessage with type CompilerMessage.Kind.deprecation. In some future release of the compiler, use of the deprecated feature will cause an error instead.

You can customize a Sass Compiler’s treatment of deprecated behaviours using a DeprecationControl to create the compiler instance. Each individual deprecation can be ignored or promoted to an error. You can also opt in to future deprecations – features that do not currently cause a deprecation warning but are planned to do so in an upcoming release of Dart Sass.

A Compiler’s deprecation settings.

Indicates which Deprecations should be fatal, silenced, or eagerly adopted.

The output from a successful compilation.

A diagnostic message generated by the Sass compiler that does not prevent the compilation from succeeding.

Appropriate for display to end users who own the stylesheets.

Thrown as an error after a failed compilation.

A section of a stylesheet.