Now if you could be convinced to make any aliases of
the mapped name be readonly (or at least readonly by
default) I would be much happier....
- joey
At 18:32 -0400 2006/08/31, Eric Iverson wrote:
The w beta for win and win64 is available.
Please get these through the web site and take a look at the new
installation instructions.
This beta includes a minor addition to mapped files (jmf.ijs) and
the mapped file lab (steps 51,52,53). Verb readonly is defined to
turn the readonly attribute of a name off and on. This can be used
to provide additional protection from errors that cause nasty
damage. If a file is mapped readonly then it can't be damaged, but
it also can't be updated. The use of readonly can restrict updates
to specific parts of an application and protect against some kinds
of damage from errors.
map file to noun data (not readonly)
1 readonly_jmf_ 'data' NB. file is read/write, but immediately mark
noun as readonly
data=: 'ooops' NB. gets an error and damage is avoided
0 readonly_jmf_ 'data' NB. allow update
do the carefully coded update
1 readonly_jmf_ 'data' NB. protect the data from unintended changes
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