5.2.2 ‘@|’: Literal vertical bar, or optional line break

In the TeX (documentation) part of a section, ‘@|’ inserts a vertical bar. This is useful inside LaTeX verbatim environments. (A simple bar would signal a shift into code mode, which is probably not what one wants.) For an example, see AT|_.

In a code part, ‘@|’ inserts an optional line break in an expression—e.g.,

‘f(a,b,@|c+d,...)’.

This helps TeX to break the line at an appropriate place. If the line does not need to be broken, the command does nothing. [Compare ‘@|’ with ‘@\’ (see ATbs) and ‘@/’ (see AT/), which always break the line.]