dvreeze / yaidom   1.13.0

Apache License 2.0 GitHub

Yet another immutable XML DOM-like API

Scala versions: 3.x 2.13 2.12 2.11 2.10
Scala.js versions: 1.x 0.6


Yaidom is a uniform XML query API, written in Scala. Equally important, yaidom provides several specific-purpose DOM-like tree implementations adhering to this XML query API. What's more, other implementations can easily be added.

Yaidom initially stood for yet another (Scala) immutable DOM-like API. Over time, the yaidom XML query API grew more important than any single DOM-like tree implementation, whether immutable or mutable. Currently, the name yaidom reflects the ease with which new DOM-like tree implementations can be added, while having them conform to the yaidom query API.

Why do we need yet another Scala (tree-oriented) XML library? After all, there are alternatives such as the standard Scala XML library. Indeed, yaidom has several nice properties:

  • the uniform XML query API, playing well with the Scala Collections API (and leveraging it internally)
  • multiple (existing or future) specific-purpose DOM-like tree implementations, conforming to this XML query API
  • among them, a nice immutable "default" DOM-like tree implementation
  • precise and first-class namespace support
  • precision, clarity and minimality in its genes, at the expense of some (but not much) verbosity and lack of XPath support
  • acceptance of some XML realities, such as the peculiarities of "XML equality" and whitespace in XML
  • and therefore no attempt to abstract JAXP away during parsing/serialization, but instead leveraging it (for parsing/serializing)
  • easy conversions between several element implementations
  • support for so-called yaidom dialects, using abstract query API traits for the backing elements and therefore supporting multiple XML backends
  • a scope mainly limited to basic namespace-aware XML processing, and therefore not offering any XSD and DTD support


Yaidom versions can be found in the Maven central repository. Assuming version 1.13.0, yaidom can be added as dependency as follows (in an SBT or Maven build):


libraryDependencies += "eu.cdevreeze.yaidom" %%% "yaidom" % "1.13.0"



Note that yaidom itself has a few dependencies, which will be transitive dependencies in projects that use yaidom. Yaidom has been cross-built for several Scala versions, leading to artifactIds referring to different Scala (binary) versions.

One transitive dependency is Saxon-HE (9.9). If Saxon-EE is used in combination with yaidom, the Saxon-HE dependency must be explicitly excluded!

Yaidom (1.8.X and later) requires Java version 1.8 or later!