EnvironmentStruct:
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Return a default data structure for SailEnvironment.
Will add the fields to an existing structure d0 if one is input.
Since version 7.
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Form:
d = EnvironmentStruct( d0 )
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Inputs
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d0 (:) Data structure, optional
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Outputs
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d (:) Data structure with environment fields
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Children:
Common: General/IsVersionAfter