Add string support to %j format.

CHANGELOG.md

@@ -17,6 +17,7 @@ All notable changes to this project will be documented in this file.
 - Allow signaling from C functions (yielding) via janet\_signalv. This
   makes it easy to write C functions that work with event loops, such as
   in libuv or embedded in a game.
+- Add '%j' formatting option to the format family of functions.
 - Add `defer`
 - Add `assert`
 - Add `when-with`

src/core/pp.c

@@ -354,6 +354,7 @@ static int print_jdn_one(struct pretty *S, Janet x, int depth) {
         case JANET_NUMBER:
         case JANET_BOOLEAN:
         case JANET_BUFFER:
+        case JANET_STRING:
             janet_description_b(S->buffer, x);
             break;
         case JANET_SYMBOL: