The sorting key. Default position is 0. If a CWL Parameter Reference
or CWL Expression is used and if the
inputBinding is associated with an input parameter, then the value of
self will be the value of the input parameter. Input parameter
defaults (as specified by the InputParameter.default field) must be
applied before evaluating the expression. Expressions must return a
single value of type int or a null.
The sorting key. Default position is 0. If a CWL Parameter Reference or CWL Expression is used and if the inputBinding is associated with an input parameter, then the value of self will be the value of the input parameter. Input parameter defaults (as specified by the InputParameter.default field) must be applied before evaluating the expression. Expressions must return a single value of type int or a null.