cat_line: 'cat()' helpers
In RonMobile/cli: Helpers for Developing Command Line Interfaces

These helpers provide useful wrappers around cat(): most importantly they all set sep = "", and cat_line() automatically adds a newline.

cat_line(..., col = NULL, background_col = NULL, file = stdout())

cat_bullet(
  ...,
  col = NULL,
  background_col = NULL,
  bullet = "bullet",
  bullet_col = NULL,
  file = stdout()
)

cat_boxx(..., file = stdout())

cat_rule(..., file = stdout())

cat_print(x, file = "")

`...`	For `cat_line()` and `cat_bullet()`, paste'd together with `collapse = "\n"`. For `cat_rule()` and `cat_boxx()` passed on to `rule()` and `boxx()` respectively.
`col, background_col, bullet_col`	Colours for text, background, and bullets respectively.
`file`	Output destination. Defaults to standard output.
`bullet`	Name of bullet character. Indexes into symbol
`x`	An object to print.

cat_line("This is ", "a ", "line of text.", col = "red")
cat_bullet(letters[1:5])
cat_bullet(letters[1:5], bullet = "tick", bullet_col = "green")
cat_rule()