Exceptions in NAnt

July 5, 2021

NAnt is an open-source build orchestration tool, written in .NET, and inspired by the Java-based Ant project. I'm mostly switching over to Cake Frosting these days, but NAnt served me very well for many years.

NAnt has limited support for exceptions, but there are a few ways we can make use of exception behaviour in our NAnt logic.

You can throw exceptions in NAnt by invoking the fail task.

<fail message="Something wrong here." />

Internally within the NAnt executor this throws a dotnet exception of type BuildException. In fact, any kind of task failure inside of NAnt ends up throwing and propagating a BuildException.

You can also catch exceptions (including any kind of task failure) using the trycatch block, as follows.

<trycatch>
    <try>
        <echo message="In try" />
        <fail message="Just because..." />
    </try>
    <catch property="failure">
        <echo message="Caught failure: ${failure}" />
        <fail message="Bad catch" />
    </catch>
    <finally>
        <echo message="Finally done" />
    </finally>
</trycatch>

Exceptions in NAnt

Further Reading