Versioning

There are multiple versions of the WDL specification. Every WDL document must include a version statement to specify which version (major and minor) of the specification it adheres to. From draft-3 forward, the first non-comment statement of all WDL files must be a version statement. For example:

version 1.2

or

#Licence header

version 1.2

A WDL file that does not have a version statement must be treated as draft-2.

Because patches to the WDL specification do not change any functionality, all revisions that carry the same major and minor version numbers are considered equivalent. For example, version 1.2 is used for a WDL document that adheres to the 1.2.x specification, regardless of the value of x.