This is a static archive of the previous Open Grid Forum Redmine content management system saved from host redmine.ogf.org file /boards/15/topics/88?r=353 at Thu, 03 Nov 2022 15:31:18 GMT Clarify the difference between %ES; and an empty DFDL string literal - Public Comments Archive - Open Grid Forum

Clarify the difference between %ES; and an empty DFDL string literal

Added by Tim Kimber about 9 years ago

Section 6.3.1: I think this wording could be clearer:

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A DFDL string literal is therefore able to describe any arbitrary sequence of bytes and characters.

Empty Strings: Empty string is not allowed as a DFDL string literal value unless explicitly stated otherwise in the description of a property. In this case the use of empty string provides some property specific behavior different from simply using the empty string as a value. When the empty string is to be used as a value, the entity %ES; must be used in the corresponding DFDL string literal."


Replies (5)

RE: Clarify the difference between %ES; and an empty DFDL string literal - Added by Tim Kimber about 9 years ago

Suggested revised wording:

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A DFDL string literal is therefore able to describe any arbitrary sequence of bytes and characters.

The special DFDL entity %ES; is provided for describing an empty string or an empty byte sequence. The %ES; entity is the only way to do this. A DFDL string literal with value "" ( the empty string ) is usually invalid. There are a few properties that explicitly allow an empty DFDL String Literal, and these properties assign a property-specific meaning to the empty string value.

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This is a static archive of the previous Open Grid Forum Redmine content management system saved from host redmine.ogf.org file /boards/15/topics/88?r=353 at Thu, 03 Nov 2022 15:31:18 GMT