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|===
a| NOTE: _WARNING:_
The Groovy 2.6 version of Groovy has been retired to focus on faster delivery of Groovy 3.0.
|===

Groovy 2.6 was intended to be a back-port of Groovy 3.0 for JDK7 but with
features requiring JDK 8 removed. Alpha versions have been released which support
the new Parrot parser (when enabled) but these versions are not feature complete wrt Groovy 3.0 functionality.
We have left the alpha versions available to help people wanting to port towards Groovy 3.0
but who are stuck on JDK7. However, we strongly encourage all users on JDK8 or above
to move directly to Groovy 3.0.
You should consult the link:../groovy-3.0.html[Groovy 3.0 release notes] for a list of supported language changes.
Only differences with 3.0 due to the different JVM requirements are reported here.

[[Groovy2.6releasenotes-Parrot]]
== Parrot Parser

Groovy 2.6 defaults to using the old parser but you can enable the Parrot parser which supports additional syntax options and language features.

=== Enabling the parser

For Groovy 3.0, the new parser is enabled by default.
However, for Groovy 2.6, you enable the new parser using a system property.
Use `-Dgroovy.antlr4=true` (set via `JAVA_OPTS` if needed).

If building from source, you need to provide Gradle with `-PuseAntlr4`
in order to include the classes which support the new parser.

== Feature differences with Groovy 3.0

Groovy 2.6 doesn't support native lambdas.

== Bundled dependencies

Groovy 2.6 optionally uses an earlier version of Ant (vs a later version in Groovy 3.0 which requires JDK8).

== JDK requirements

Groovy 2.6 requires JDK8+ to build and JDK7 (vs JDK8 for Groovy 3.0) is the minimum version of the JRE that we support.

[[Groovy2.6releasenotes-Moreinformation]]
== More information

You can browse all the link:../changelogs/changelog-2.6.0-alpha-1.html[tickets closed for Groovy 2.6 in JIRA].