[libgda] Misc GdaNumeric related improvements

[Vivien Malerba <vivien src gnome org>]

commit cb30ac58230afe053824e4c3d9ecc5a4fb82db41
Author: Vivien Malerba <malerba gnome-db org>
Date:   Fri Dec 20 19:24:57 2013 +0100

    Misc GdaNumeric related improvements

 libgda/gda-value.c |   31 ++++++++++++++++---------------
 libgda/gda-value.h |    8 ++++----
 2 files changed, 20 insertions(+), 19 deletions(-)
---
diff --git a/libgda/gda-value.c b/libgda/gda-value.c
index 6dcc31c..f45026d 100644
--- a/libgda/gda-value.c
+++ b/libgda/gda-value.c
@@ -68,11 +68,11 @@ extern gchar *gda_numeric_locale;
  * This struct must be considered as opaque. Any access to its members must use its
  * accessors added since version 5.0.2.
  *
- * Set value func: gda_value_set_numeric
- * Get value func: gda_value_get_numeric
+ * Set value func: gda_value_set_numeric()
+ * Get value func: gda_value_get_numeric()
  */
 struct _GdaNumeric {
-       gchar*   number;
+       gchar*   number; /* stored in the "C" locale, never NULL */
        glong    precision;
        glong    width;
        
@@ -991,10 +991,11 @@ gda_numeric_set_width (GdaNumeric *numeric, glong width)
  * Gets the width of a #GdaNumeric. (Not yet implemented).
  *
  * Returns: an integer with the width of a #GdaNumeric. (Not jet implemented).
+ *
  * Since: 5.0.2
  */
 glong
-gda_numeric_get_width (GdaNumeric *numeric)
+gda_numeric_get_width (const GdaNumeric *numeric)
 {
        g_return_val_if_fail (numeric, 0.0);
        return numeric->width;
@@ -1023,10 +1024,11 @@ gda_numeric_set_precision (GdaNumeric *numeric, glong precision)
  * Gets the precision of a #GdaNumeric.
  *
  * Returns: an integer with the precision of a #GdaNumeric.
+ *
  * Since: 5.0.2
  */
 glong
-gda_numeric_get_precision (GdaNumeric *numeric)
+gda_numeric_get_precision (const GdaNumeric *numeric)
 {
        g_return_val_if_fail (numeric, -1);
        return numeric->precision;
@@ -1035,16 +1037,19 @@ gda_numeric_get_precision (GdaNumeric *numeric)
  * gda_numeric_get_string:
  * @numeric: a #GdaNumeric
  *
- * Get the string representation of @numeric.
+ * Get the string representation of @numeric, in the C locale format (dot as a fraction separator).
  *
  * Returns: (transfer full) (allow-none): a new string representing the stored valued in @numeric
+ *
  * Since: 5.0.2
  */
 gchar*
-gda_numeric_get_string (GdaNumeric *numeric)
+gda_numeric_get_string (const GdaNumeric *numeric)
 {
-       g_return_val_if_fail (numeric, NULL);
-       return g_strdup (numeric->number);
+       if (numeric)
+               return g_strdup (numeric->number);
+       else
+               return NULL;
 }
 
 /*
@@ -2671,12 +2676,8 @@ gda_value_compare (const GValue *value1, const GValue *value2)
                        else
                                retval = 1;
                }
-               else {
-                       if (num2->number)
-                               retval = -1;
-                       else
-                               retval = 0;
-               }
+               else
+                       retval = -1;
                return retval;
        }
 
diff --git a/libgda/gda-value.h b/libgda/gda-value.h
index d84ed82..f537940 100644
--- a/libgda/gda-value.h
+++ b/libgda/gda-value.h
@@ -263,12 +263,12 @@ GdaNumeric*                       gda_numeric_new (void);
 GdaNumeric*                       gda_numeric_copy (GdaNumeric *src);
 void                              gda_numeric_set_from_string (GdaNumeric *numeric, const gchar* str);
 void                              gda_numeric_set_double (GdaNumeric *numeric, gdouble number);
-gdouble                           gda_numeric_get_double (GdaNumeric *numeric);
+gdouble                           gda_numeric_get_double (const GdaNumeric *numeric);
 void                              gda_numeric_set_precision (GdaNumeric *numeric, glong precision);
-glong                             gda_numeric_get_precision (GdaNumeric *numeric);
+glong                             gda_numeric_get_precision (const GdaNumeric *numeric);
 void                              gda_numeric_set_width (GdaNumeric *numeric, glong width);
-glong                             gda_numeric_get_width (GdaNumeric *numeric);
-gchar*                            gda_numeric_get_string (GdaNumeric *numeric);
+glong                             gda_numeric_get_width (const GdaNumeric *numeric);
+gchar*                            gda_numeric_get_string (const GdaNumeric *numeric);
 void                              gda_numeric_free (GdaNumeric *numeric);
 
 GType                             gda_time_get_type (void) G_GNUC_CONST;