Raul Miller <[email protected]> wrote:
> >> My reading of these two concepts suggests that x and y are sometimes
> >> prohibited as global names. ?And, it's easy enough to conduct an
> >> experiment to test this concept:
> >>
> >> ? 3 :'y=:0' 0
> >> |domain error
> >> | ? y ? ?=:0
> >
> >
> > This is not because y is forbidden as a global name.
>
> I do not think that "sometimes prohibited" and "forbidden" mean the same
> thing.
Use of global x and y is NEVER prohibited. They are just more difficult to
access, since one and/or the other is always masked by a local variable
within any explicit definition. However, these can easily be circumvented
by use of locales, or by stepping out of the definition, or using only tacit
verbs.
x =: 4
y =: 3
X =: 3 :'x'
Y =: 3 :'0(1 :''y'')'
v =: 4 : '(X+Y)0'
10 v 20
7
w =: 4 : 'x__+y__'
10 w 20
7
t =. ".@:('x'"_) + ".@:('y'"_)
10 t 20
7
-- Mark D. Niemiec <[email protected]>
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