Wait... 'control error' is detected during preparse(). We wouldn't want
to defer that till execution, at least not by default. Would you want a
foreign to control when preparse is executed?
Henry
On 6/21/2016 9:17 PM, bill lam wrote:
Thank you for the information on jtpreparse(). I notice it took a
long time to load scripts, eg, I have a script of size about 3MB that
took 3 to 10 second to load. If/when your work on "first
execution" can be done, will it be possible to add another global parameter
to defer jtpreparse() to the first execution (current behavior
is good for development).
Вт, 21 июн 2016, Henry Rich написал(а):
I agree with your logic, but there is a problem, which I am encountering
while working on something else.
[And also FYI, a considerable amount of processing is done when a definition
is loaded, in jtpreparse(), which maps out all the control words]
I am working on an overhaul of symbol-table operations to (1) make
references to local symbols much faster; (2) avoid the overhead of
allocate/fill/free that currently occurs every time an explicit definition
is executed.
My approach is to create a symbol table and let it hang around after
execution, to be used next time the definition runs.
I wanted to create this table on first execution, just as you suggest, but
my problem is, How do I point to it? It's not easy to create a new data
structure in the JE, and the explicit definition seems to use all the fields
except gs which I think needs to be kept at 0.
The hs field points to a 6-box array containing the results of preparse().
I can add my new symbol table there, but then I need to make sure its
usecounts are the same as the rest of hs, because otherwise as the verb gets
assigned or deleted I might lose the symbol table.
So, I have to create the symbol table at load time, the same time preparse()
runs. There's just no way I can see to wait till the first execution. I
don't think the overhead is material for the local symbol table. It might
be a different story for preparsed parenthesized nouns.
Henry
On 6/21/2016 8:12 PM, bill lam wrote:
IMO only small portion of code (say 20%) of a non-trival program
will be actively used. The extra time needed for loading
scripts that will seldom used is wasteful. Perhaps you may
defer to pre-parse stage to the first execution of explicait
definition. Timing benchmark is helpful here.
I worry the extra space allocated that will not freed, a promise
would be affect expressions that involving no nouns (other than
primitive nouns a. a:)
Since this is an implementation detail, not a language feature,
I think it should be turn on/off by a global parameter.
Пн, 20 июн 2016, Henry Rich написал(а):
It occurs to me that in explicit definitions, parenthesized expressions that
contain only primitives could be parsed at definition time and replaced with
a single word in the queue. This would save parsing time during execution.
The only downside I can see is that something like (<1000 1000 $ a:) would
tie up a lot of memory - maybe I would have to check for that.
Any other objections?
Henry
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