printerr -- print something to stderr

Synopsis

Print x, each line prepended with --, to stderr. This is useful for displaying warning messages and verbose logs.

i1 : printerr "Hello, world!"
 -- Hello, world!

i2 : printerr("foo" || "bar")
 -- foo
 -- bar

If x is a basic list, then its elements are first joined with horizontalJoin.

i3 : printerr("foo", "bar")
 -- foobar