Yay, that works unlike EVERY SINGLE EXAMPLE I COULD FIND ONLINE.

ALthough I'm now trying to figure out what to do with the two-word keys, because post author, "post author," 'post author,' [post author], and (post author) don't seem to work.

edit: FIXED. For some reason, print_f(array) left the underscores between the two words in the two-word keys out, while print_r(array) showed them, so they're actually post_author, post_date, etc. GAH TWO HOURS OF MY LIFE WASTED