`for`. The `${}` form is a Javascript function, which can include
control blocks, and must end in a `return` statement.
-Dxpressions can both appear in `valueFrom` fields as well as some
+Expressions can both appear in `valueFrom` fields as well as some
other fields, or in an `ExpressionTool` which, like `Workflow` or
`CommandLineTool` has explicitly defined `inputs` and `outputs`
sections.
> bam files.
>
{: .challenge }
+
+> ## Episode solution
+> * <a href="../assets/answers/ep6/main.cwl">main.cwl</a>
+> * <a href="../assets/answers/ep6/alignment.cwl">alignment.cwl</a>
+> * <a href="../assets/answers/ep6/featureCounts.cwl">featureCounts.cwl</a>
+> * <a href="../assets/answers/ep6/subdirs.cwl">subdirs.cwl</a>
+{: .solution}