This is a Web patch file for tex.
The change file adds a new primitive called \quitvmode. In vertical modes, it is identical to \indent, but in horizontal and math modes it is identical to \noindent.
An \indent encountered in horizontal or math mode adds an `indentation box', much like TeX would have done if it had been in vertical mode.
This indentation-sized whitespace box is often undesirable, but it's appearance cannot be circumvented without a new primitive.
The change file