Hi,
as an exercise, I decided to make a simple "like" operator
like=:([:*./([=])+.('?'E.]))
NB. in english: get membership flags where '?' is in the set y
NB. OR that with the comparison flags
NB. *./ insert-AND to get the result
the problem with this "like" operator is that x and y portions must be the
same length. For example:
'abcaabc' like 'abc?abc'
1
'Abcaabc' like 'abc?abc'
0
'abcaabc' like 'abc?ab'
|length error --- NB. fair enough that's how equals '=' is defined
Is there an easy way to do guard conditionally, but to do this tacitly? i.e.
the lengths are different, so return fail/zero?
ideas so far:
* email the list without fully exploring the possibilities ;)
* look at J's regex library (did this a little)
* implement something like "stretch=: [$],($,:@{:)" but with an unlikely
non-ASCII character (hack so *bad*).
* convert characters to numbers. move elements to a 2D array pre-filled
with null whose right bound is the max of #x,#y (i.e. >/ (#x,#y). Continue
on from there. create various verbs + flatten it afterwards to get tacit
version. (not done yet).
thanks,
-Steven
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