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Added documentation for packed pragma

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Audun Wilhelmsen 2014-03-20 23:11:33 +01:00
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doc/manual.txt
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@ -5390,6 +5390,11 @@ checked.
**Future directions**: GC'ed memory should be allowed in unions and the GC **Future directions**: GC'ed memory should be allowed in unions and the GC
should scan unions conservatively. should scan unions conservatively.
Packed pragma
-------------
The `packed`:idx: pragma can be applied to any ``object`` type. It ensures that the fields of an object is packed back-to-back in memory. It is useful to store packets or messages from/to network or hardware drivers, and for interoperability with C. Combining packed pragma with inheritance is not defined, and it should not be used with GC'ed memory (ref's).
**Future directions**: Using GC'ed memory in packed pragma will result in compile-time error. Usage with inheretinence should be defined and documented.
Unchecked pragma Unchecked pragma
---------------- ----------------

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web/news.txt
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@ -61,6 +61,7 @@ News
evaluation. evaluation.
- ``--gc:none`` produces warnings when code uses the GC. - ``--gc:none`` produces warnings when code uses the GC.
- A ``union`` pragma for better C interoperability is now supported. - A ``union`` pragma for better C interoperability is now supported.
- A ``packed`` pragma to control the memory packing/alignment of fields in an object.
- Arrays can be annotated to be ``unchecked`` for easier low level - Arrays can be annotated to be ``unchecked`` for easier low level
manipulations of memory. manipulations of memory.