# why do some backslashes disappear in a quote?

in this answer, one of the quotes contains some latex code:

For example: $x^2$ vs (^2) ...

by which is meant

For example: $x^2$ vs $$^2$$ ...

the original input doesn't use backticks to indicate the code (check it out via the edit function), but even so, the backslashes shouldn't disappear -- they don't disappear in other quotes in the same answer, e.g.

Other examples: \it vs the more modern \itshape ...

this sure looks like a bug to me.

(i didn't find any existing tag for "quote" so i concocted one. feel free to rephrase or otherwise improve it.)

edit: for the benefit of others who might run into the same problem, the list that Werner gives in his answer appears to be complete (and yes, backslash escaping applies to curly braces as well as to parentheses and brackets). if you want a backslash to appear before one of these characters in a quote block without using backticks, double the backslash: \$$... \$$

$$...$$

there's a formatting sand-box for trying out things like this. (i should have looked there first.) it's community wiki, so don't be afraid of making an addition if you discover something new -- it could help the terminally confused, like me.

This all has to do with the fact that SE uses markdown in posts and comments (similar to setting some character's catcode to \active), and markdown uses the following set of characters that have special meaning:

• [, ] Used with links/internal references/tags
• (, ) Used with links/internal references
• # Headings
• ! Images, language syntax formatting and spoilers
• *, -, + Lists, rules and emphasis
• \ Escaping
• . Short-hand links to network sites (like [tex.se])
• > Block quoting and HTML
•  Inline code
• _ Rules
• {, } ???

All of the above are "escapable" via \`.

See Markdown help or the official Markdown syntax reference page for more detail.

• thanks -- that's some pretty heavy weekend reading. nothing helpful for this problem in the first reference, but the second does have it. (only problem i have is physical -- bad reverse video on my monitor -- but i'll figure out something to get around that.) – barbara beeton Dec 18 '13 at 19:37