My problem is, I have a class 'A' say. and I have a locale 'B'.
A contains several verbs. I would like to pass a verb (or gerunds of the
verbs), let's call it myVerb, to some verb in B. However, this creates a
problem, as
when the B verb tries to call myVerb it cannot find it, being in a different
locale. i.e. I get a value error. I attempted to use fix (f.) to get myVerb
explicitly, but this only
works if myVerb does not contain any other verbs from A.
This is the contrived example, that is essentially the same as my real problem,
but stripped of superfluous things:
NB. A is some class with several verbs.
coclass 'A'
create=: 3 : 0
d=:y
)
NB. some verb in A
geoMean=: 3 : 0
(#%:(*/)) y
)
NB. I want to pass this to another verb in another locale.
NB. Note that it calls geoMean.
myVerb =: 3 : 0
((geoMean f.) ; (+/%#)) y
)
NB. calling a verb in B
getAvg=: 3 : 0
data=.y
funcB_B_ ( myVerb f. `''); data
)
NB. create my instance of A
myA =: 0 conew 'A'
NB. call myVerb. No problem here!
myVerb__myA 1 2 3
NB. pass myVerb to funcB_B_
getAvg__myA 1 2 3
NB. this gives an error
|value error: geoMean
| ((geoMean f.);(+/%#))y
Solutions:
(1) One solution is to make funcB_B_ a conjunction / adverb. But in reality, I
want to send several verbs to funcB together.
(2) Another solution is to send the instance reference of A to funcB (i.e. just
send the whole of myA to funcB). But I would prefer not to send the whole
object, as it then makes B less flexible, because I may want to call funcB_B_
without the need for a class instance, just a standalone verb.
(3) Another solution is to not call any other verbs of myA inside myVerb__myA.
This is not a realistic solution as A could be quite complicated.
Is there a better way?
Just to explain my motivation, I am trying to replicate the functionality most
languages that have first-class functions possess - to pass arbitrary
function(s) to
other functions and call them.
e.g. in Python
# myVerb is a Python function, and could be a member method of some class.
someData is just some data
def funcB (myVerb, someData):
return myVerb(someData, someOtherData)
Obviously J doesn't have first class functions in this sense, but with gerunds,
I was hoping to be able to recreate the functionality.
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