X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=src%2Flanguage%2Flexer%2Fvariable-parser.c;h=5c19b81e2f5bd8c477f80742464416b8a58f8fb2;hb=4ace3e978177b9f189ac8ebf8e852d5001dabcf5;hp=49d6a5deb900a6e63e8363b1fd020c685116f16c;hpb=2be9bee9da6a2ce27715e58128569594319abfa2;p=pspp

diff --git a/src/language/lexer/variable-parser.c b/src/language/lexer/variable-parser.c
index 49d6a5deb9..5c19b81e2f 100644
--- a/src/language/lexer/variable-parser.c
+++ b/src/language/lexer/variable-parser.c
@@ -37,6 +37,8 @@
 #include "libpspp/str.h"
 #include "libpspp/stringi-set.h"
 
+#include "math/interaction.h"
+
 #include "gl/c-ctype.h"
 #include "gl/xalloc.h"
 
@@ -873,3 +875,70 @@ var_set_create_from_array (struct variable *const *var, size_t var_cnt)
   return vs;
 }
 
+
+/* Match a variable.
+   If the match succeeds, the variable will be placed in VAR.
+   Returns true if successful */
+bool
+lex_match_variable (struct lexer *lexer, const struct dictionary *dict, const struct variable **var)
+{
+  if (lex_token (lexer) !=  T_ID)
+    return false;
+
+  *var = parse_variable_const  (lexer, dict);
+
+  if ( *var == NULL)
+    return false;
+  return true;
+}
+
+/* An interaction is a variable followed by {*, BY} followed by an interaction */
+static bool
+parse_internal_interaction (struct lexer *lexer, const struct dictionary *dict, struct interaction **iact, struct interaction **it)
+{
+  const struct variable *v = NULL;
+  assert (iact);
+
+  switch  (lex_next_token (lexer, 1))
+    {
+    case T_ENDCMD:
+    case T_SLASH:
+    case T_COMMA:
+    case T_ID:
+    case T_BY:
+    case T_ASTERISK:
+      break;
+    default:
+      return false;
+      break;
+    }
+
+  if (! lex_match_variable (lexer, dict, &v))
+    {
+      if (it)
+	interaction_destroy (*it);
+      *iact = NULL;
+      return false;
+    }
+  
+  assert (v);
+
+  if ( *iact == NULL)
+    *iact = interaction_create (v);
+  else
+    interaction_add_variable (*iact, v);
+
+  if ( lex_match (lexer, T_ASTERISK) || lex_match (lexer, T_BY))
+    {
+      return parse_internal_interaction (lexer, dict, iact, iact);
+    }
+
+  return true;
+}
+
+bool
+parse_design_interaction (struct lexer *lexer, const struct dictionary *dict, struct interaction **iact)
+{
+  return parse_internal_interaction (lexer, dict, iact, NULL);
+}
+