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+# Symbols and strings, revisited
+
+My [original plan](symbols.html) was to make strings and symbols one
+and the same.  Then I realized this introduced ambiguity between bare
+strings meant as identifiers, and quoted strings representing a string
+literal in code.
+
+After a bunch of back-and-forth, I came up with the idea of the Zisp
+[decoder](reader.html) with which I'm very happy overall, but I still
+decided to ditch the idea of using an intermediate representation for
+quoted string literals like `(#STRING . "foo")` after all.
+
+The idea was that the reader would have a data mode and a code mode
+and that quoted strings would become `(#STRING . "foo")` or such in
+code mode, but not in data mode.  This way, reading a configuration
+file (in data mode) that uses quoted strings would not end up giving
+you this wonky thing with `#STRING`.
+
+It was an exciting idea at first, but eventually I realized that the
+above was the *only* substantial reason to have separate modes for
+reading s-expressions.  It also annoyed me a bit that every single
+quoted string in code would be wrapped in a cons cell...
+
+So, ultimately I've decided to simply make quoted strings a proper
+sub-type of strings.  (Or make symbols a sub-type of strings; which
+ever way you want to look at it.)
+
+Also, my [NaN-packing strategy](nan.html) has so much extra room that
+I've decided to put up-to-6-byte strings into NaNs as an optimization
+hack, and this applies to both quoted and bare strings.
+
+So we have two different string types, and two different in-memory
+representations for each.  Let's summarize and give them names:
+
+* sstr: Short string (symbol, up to 6 bytes)
+
+* qstr: Quoted short string (non-symbol, up to 6 bytes)
+
+* istr: Interned string (symbol, greater than 6 bytes)
+
+* ustr: Uninterned string (non-symbol, greater than 6 bytes)
+
+Don't get hung up on the short four-letter names; they aren't fully
+descriptive.  The "qstr" isn't the only one representing a quoted
+string literal; a "ustr" may also represent one.
+
+Here's how the parser uses these types:
+
+* Encountered an unquoted string of up to 6 bytes?  Make a sstr.
+
+* Encountered a quoted string of up to 6 bytes?  Make a qstr.
+
+* Unquoted string of more than 6 bytes?  Intern it to make an istr.
+
+* Quoted string of more than 6 bytes?  Uninterned string.
+
+*** WIP ***