Tab Resistant Formatting Note

A set of conventions to avoid problems of tabs being converted back and forth between spaces or tabs in various editors/browsers. This topic marker can be used to explain the presence of "funny characters" in ASCII diagrams or examples.

Possible Conventions

Don't allow any spaces in ASCII diagrams. Replace them with periods or underlines if you have to.
Start the left edge with same character in the same position.

DavidCary uses this convention:

Don't use any tabs "inside" ASCII diagrams. Use spaces. Tabs at the left edge are OK.
Make sure there is at least once space character at the beginning of every line of the entire ASCII diagram (even blank lines start with one space, if it's in the middle of the diagram).