nofill – Preserve spaces and line breaks when setting text
The commands \fill and \nofill bracket text in which multiple spaces are not collapsed into a single space, and spaces at the start of line are preserved.
Maybe you are interested in the following packages as well.
- idverb: Inline verbatim identifiers
- verbtim2: Verbatim listings in Plain TeX
- verbatim-pln: Define new verbatim "environments" in Plain TeX
- astyped: Verbatim environment, with rather few escapes