Re: "Can't break line warning"

[Tadziu Hoffmann]

> The horizontal line output by the \l escape is 6 inches, the same as the
> declared line length.
> troff: letterhead-demo.mm:31: warning [p 1, 0.5i]: can't break line

You have a tab after the "\l'6i'", which counts as part of the
line.  Remove it, and the error disappears.

  \s+5World Reknowned Corporation\s0
  .br
  \u\l'6i'\" Horizontal line @ 6 inches
  .tl '''\u\s-24927 33\*[SUP]rd\*[SUPX] Street, Megalopolis, KS 67999\s0'
  .sp 3

You then need to put a ".br" after the line, to terminate it,
otherwise it's retained as a partially filled line until the
next break (from the ".sp 3"), and therefore is only output
after the 3-part title.

  \s+5World Reknowned Corporation\s0
  .br
  \u\l'6i'\" Horizontal line @ 6 inches
  .br
  .tl '''\u\s-24927 33\*[SUP]rd\*[SUPX] Street, Megalopolis, KS 67999\s0'
  .sp 3

Alternatively, do the right-adjusting with ".rj" instead of ".tl":

  \s+5World Reknowned Corporation\s0
  .br
  \u\l'6i'\" Horizontal line @ 6 inches
  .rj 1
  \u\s-24927 33\*[SUP]rd\*[SUPX] Street, Megalopolis, KS 67999\s0
  .sp 3