+bool value_is_spaces (const union value *, int width);
+
+static inline void value_swap (union value *, union value *);
+
+struct pool;
+void value_init_pool (struct pool *, union value *, int width);
+void value_clone_pool (struct pool *, union value *, const union value *,
+ int width);
+void value_resize_pool (struct pool *, union value *,
+ int old_width, int new_width);
+\f
+/* Initializes V as a value of the given WIDTH, where 0
+ represents a numeric value and a positive integer represents a
+ string value WIDTH bytes long.
+
+ A WIDTH of -1 is ignored.
+
+ The contents of value V are indeterminate after
+ initialization. */
+static inline void
+value_init (union value *v, int width)
+{
+ if (width > 0)
+ v->s = xmalloc (width);
+}
+
+/* Initializes V as a value of the given WIDTH, as with value_init(), and
+ copies SRC's value into V as its initial value. */
+static inline void
+value_clone (union value *v, const union value *src, int width)
+{
+ if (width <= 0)
+ v->f = src->f;
+ else
+ v->s = xmemdup (src->s, width);
+}
+
+/* Returns true if a value of the given WIDTH actually needs to
+ have the value_init and value_destroy functions called, false
+ if those functions are no-ops for values of the given WIDTH.
+
+ Using this function is only a valuable optimization if a large
+ number of values of the given WIDTH are to be initialized*/
+static inline bool
+value_needs_init (int width)
+{
+ return width > 0;
+}
+
+/* Same as value_init, except that failure to allocate memory
+ causes it to return false instead of terminating the
+ program. On success, returns true. */
+static inline bool
+value_try_init (union value *v, int width)
+{
+ if (width > 0)
+ {
+ v->s = malloc (width);
+ return v->s != NULL;
+ }
+ else
+ return true;
+}
+
+/* Frees any memory allocated by value_init for V, which must
+ have the given WIDTH. */
+static inline void
+value_destroy (union value *v, int width)
+{
+ if (width > 0)
+ free (v->s);
+}
+
+/* Copies SRC to DST, given that they both contain data of the
+ given WIDTH. */
+static inline void
+value_copy (union value *dst, const union value *src, int width)
+{
+ if (width <= 0)
+ dst->f = src->f;
+ else
+ memcpy (dst->s, src->s, width);
+}
+
+/* Exchanges the contents of A and B. */
+static inline void
+value_swap (union value *a, union value *b)