As far as possible each single character key-definition corresponds to where that character is on the keyboard (a is `a', etc...).
When using an Amiga this should be true for all keys since the Amiga's "keymap.library" makes it easy to look up what key a character belongs to. However, this is not so easy on X11. All of the standard ASCII character set should be okay, but the more esoteric characters may have to be specified by the names of their X11 keysym (without the `XK_' prefix). Look in the <X11/keysymdef.h> include file for all keysyms, for example `XK_question' would have to be used for `?' if the editor didn't treat it, and many others, specially.
Some keys which don't follow this pattern are
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