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Monadic 0N!

Write to console and return.

Syntax: 0N!x

Returns x after printing its unformatted representation to the console.

o)0N!"first\nsecond"
"first\nsecond"
"first\nsecond"
o)println "first\nsecond"
first
second
o)

With 0N! you can see the current vаlue of any part of the expression. It useful for debugging.

o)*/0N!1+0N!!5
0 1 2 3 4
1 2 3 4 5
120
o)

Results of print, println, show and 0N! can be redirected. -1! works like 0N! but non-redirectable.
r:reagent[`async];
oldout:@[{.o.out};0N;0N];
//redirect stdout to `async reagent
.o.out::r;
0N!"test 0N!";
-1!"test -1!";
//stop redirecting
.o.out::oldout;
println "";
println get r;

"test -1!"

"test 0N!"
You can redirect STDERR with .o.err. -2! write to STDERR and return result without redirection.