showln(@key stream = current_writer(), quotes = false, obj1, ...)
Write the textual representation of the objects obj1 ... to the output-stream stream.
If quotes is true, output the enclosing quotes for strings and symbols.
After writing obj1 ..., output a line-feed character (newline) and return void.
showln("hello, world")
//> hello, world
showln(quotes = true, "hello, world")
//> "hello, world"
let f = file_writer("abc.txt")
call_with_stream(f, ^(f) showln(stream = f, quotes = true,
[1, 2, 3],
#{'a: "hello", 'b: 123}))
close_writer(f)
// the contents of abc.txt will be: [1, 2, 3]#{'b: 123, 'a: "hello"}