The conjunction @: turns u@:v into a single verb whereas u v alone
represent 2 verbs. Sticking @: into a train converts a hook into a
fork, a fork into an hook, and changes verb valence. Let's examine your
A and B proverbs.
with_at=:(+/ % #) , *:@:+:
sans_at=:(+/ % #) , *: +:
with_at
(+/ % #) , *:@:+:
sans_at
(+/ % #) (, *: +:)
Wow!
The with_at case guarantees squaring, the monadic definition of *: .
Without @: the *: appears as an even verb of a fork, hence dyadic,
which is "not and" with Boolean domain. Thus domain error.
Date: Thu, 16 Apr 2015 05:19:09 -0400
From: "Linda Alvord"<lindaalv...@verizon.net>
To:<programm...@jsoftware.com>
Subject: Re: [Jprogramming] Verb to string and Verb array
Message-ID:<000c01d07826$68500770$38f01650$@verizon.net>
Content-Type: text/plain; charset=utf-8
Why is @: necessary?
(1 {A=:(+/ % #) , *:@:+:) 1 2 3
4
A
(+/ % #) , *:@:+:
A 1 2 3
2 4 16 36
(1 {B=:(+/ % #) , *:+:) 1 2 3
|domain error
| (1{B=:(+/%#),*:+:)1 2 3
B
(+/ % #) (, *: +:)
Linda
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