Clean up how transformations work.

[pspp] / src / language / xforms / sample.c

diff --git a/src/language/xforms/sample.c b/src/language/xforms/sample.c
index 260841a6029b541ddd97dc3ca811391dfee68471..665cd4468edc370e80390441cb27d1ddb9fa3f27 100644 (file)
--- a/src/language/xforms/sample.c
+++ b/src/language/xforms/sample.c
@@ -51,8 +51,7 @@ struct sample_trns
     unsigned frac;              /* TYPE_FRACTION: a fraction of UINT_MAX. */
   };
 
-static trns_proc_func sample_trns_proc;
-static trns_free_func sample_trns_free;
+static const struct trns_class sample_trns_class;
 
 int
 cmd_sample (struct lexer *lexer, struct dataset *ds)
@@ -88,17 +87,9 @@ cmd_sample (struct lexer *lexer, struct dataset *ds)
       lex_get (lexer);
       if (!lex_force_match_id (lexer, "FROM"))
        return CMD_FAILURE;
-      if (!lex_force_int (lexer))
+      if (!lex_force_int_range (lexer, "FROM", a + 1, INT_MAX))
        return CMD_FAILURE;
       b = lex_integer (lexer);
-      if (a >= b)
-       {
-         msg (SE, _("Cannot sample %d observations from a population of "
-                    "%d."),
-              a, b);
-         return CMD_FAILURE;
-       }
-
       frac = 0;
     }
   lex_get (lexer);
@@ -109,13 +100,13 @@ cmd_sample (struct lexer *lexer, struct dataset *ds)
   trns->N = b;
   trns->m = trns->t = 0;
   trns->frac = frac;
-  add_transformation (ds, sample_trns_proc, sample_trns_free, trns);
+  add_transformation (ds, &sample_trns_class, trns);
 
   return CMD_SUCCESS;
 }
 
 /* Executes a SAMPLE transformation. */
-static int
+static enum trns_result
 sample_trns_proc (void *t_, struct ccase **c UNUSED,
                   casenumber case_num UNUSED)
 {
@@ -154,3 +145,9 @@ sample_trns_free (void *t_)
   free (t);
   return true;
 }
+
+static const struct trns_class sample_trns_class = {
+  .name = "SAMPLE",
+  .execute = sample_trns_proc,
+  .destroy = sample_trns_free,
+};