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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