+ /**
+ * This is equivalent to {@link YangStatementLexer#SEP}'s definition. Currently equivalent to the non-repeating
+ * part of:
+ *
+ * <p>
+ * {@code SEP: [ \n\r\t]+ -> type(SEP);}.
+ */
+ private static final CharMatcher SEP = CharMatcher.anyOf(" \n\r\t").precomputed();
+
+ /**
+ * Splitter corresponding to {@code key-arg} ABNF as defined
+ * in <a href="https://tools.ietf.org/html/rfc6020#section-12">RFC6020, section 12</a>:
+ *
+ * <p>
+ * {@code key-arg = node-identifier *(sep node-identifier)}
+ *
+ * <p>
+ * We also account for {@link #SEP} not handling repetition by ignoring empty strings.
+ */
+ private static final Splitter KEY_ARG_SPLITTER = Splitter.on(SEP).omitEmptyStrings();
+