Once you surround 3 verbs by ( ) you have defined a ‘verb train’ (called a fork
for 3 verbs).
The definition of a monadic fork is:
(f g h) y <==> (f y) g (h y)
Consider:
( + , * ) 123
123 1 NB. Ie (+123),(*123)
In your case:
(><]) 123
0 NB. As the expression is equivalent to (>123) < (] 123) ...
which is 123<120, hence 0 as the middle verb is ‘less than’ (not box).
To achieve what you require you can either do:
>@:< 123
123
Or…
([: > <) 123
123
Read in Nuvoc about hooks, forks, trains and the use of [: (Cap)
Cheers, Rob
> On 2 Jul 2022, at 9:26 pm, Jacques Bailhache <jacques.bailha...@gmail.com>
> wrote:
>
> According to https://www.jsoftware.com/help/dictionary/d020.htm :
> Open is the inverse of box, that is, ><y is y .
> But :
> ] 123
> 123
> (><]) 123
> 0
> (>(<])) 123
> 1
> How do you explain I get different results ?
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