+/*
+ * Look up the value of `Lb' for matching predefined strings. If it has
+ * one, then substitute the current value for the formatted value. Note
+ * that the lookup may fail (we can provide arbitrary strings).
+ */
+/* ARGSUSED */
+static int
+post_lb(POST_ARGS)
+{
+ const char *p;
+ char *buf;
+ size_t sz;
+
+ assert(MDOC_TEXT == n->child->type);
+ p = mdoc_a2lib(n->child->string);
+
+ if (p) {
+ free(n->child->string);
+ n->child->string = mandoc_strdup(p);
+ return(1);
+ }
+
+ sz = strlen(n->child->string) +
+ 2 + strlen("\\(lqlibrary\\(rq");
+ buf = mandoc_malloc(sz);
+ snprintf(buf, sz, "library \\(lq%s\\(rq", n->child->string);
+ free(n->child->string);
+ n->child->string = buf;