[Jprogramming] fsm suggestion. ew when j=_1 should emit empty box/word

[Raul Miller]

I have been wishing for an option to get the first of the s columns of
the trace. Currently, you can use (5;...) and index column 4, but i
anticipate it being significantly faster (and more order-of-magnitude
more space efficient) to just get the one column.

The point being that it can be useful to analyze a body of text using
;: and extract the state of each character (state being the row# which
will handle the next character). (Note that the parsing operation is
mostly irrelevant, here, except as something that happens to exist.)

Thanks,

-- 
Raul



On Thu, Mar 23, 2017 at 5:18 PM, Henry Rich <henryhrich at gmail.com> wrote:
> I would like to throw the discussion open to ways to generalize FSM, perhaps
> by invoking a user-defined emit verb.
>
> Henry Rich
>
>
> On 3/23/2017 5:10 PM, 'Pascal Jasmin' via Programming wrote:
>>
>> I understand that current behaviour is to crash with index error if an ew
>> action is invoked while j=_1
>>
>> It would actually be extremely convenient to emit an empty box (word)
>> instead.  I'm unsure that a crash is helpful.
>>
>> One use case is splitting words by parentheses groups (without the outter
>> parentheses), such that only odd indexes are paren groups.  The workaround
>> is to append an empty box if leading char is (, and to replace ')('
>> (consecutive close then open) strings with a sequence of nulls long enough
>> to not have likely occurred with natural probability.
>>
>> setting j=0 on start is not allowed, because it must be smaller than i.
>>
>> ew on first char ( (empty word) would work well.  Because I wish to
>> discard closing ), ew on immediately following ( (again empty word) with a (
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