+#if defined (DPAREN_ARITHMETIC)
+/* The arithmetic evaluation command, ((...)). Just a set of flags and
+ a WORD_LIST, of which the first element is the only one used, for the
+ time being. */
+typedef struct arith_com {
+ int flags;
+ WORD_LIST *exp;
+ int line;
+} ARITH_COM;
+#endif /* DPAREN_ARITHMETIC */
+
+/* The conditional command, [[...]]. This is a binary tree -- we slippped
+ a recursive-descent parser into the YACC grammar to parse it. */
+#define COND_AND 1
+#define COND_OR 2
+#define COND_UNARY 3
+#define COND_BINARY 4
+#define COND_TERM 5
+#define COND_EXPR 6
+
+typedef struct cond_com {
+ int flags;
+ int line;
+ int type;
+ WORD_DESC *op;
+ struct cond_com *left, *right;
+} COND_COM;
+