From 278036081ff0218eaea082903ea81e9a1b725e94 Mon Sep 17 00:00:00 2001
From: LtWorf <LtWorf@014f5005-505e-4b48-8d0a-63407b615a7c>
Date: Wed, 5 Nov 2008 17:18:28 +0000
Subject: [PATCH] Changed internal rename method. Now uses a dictionary

git-svn-id: http://galileo.dmi.unict.it/svn/relational/trunk@50 014f5005-505e-4b48-8d0a-63407b615a7c
---
 CHANGELOG   |  3 ++-
 parser.py   |  4 ++--
 relation.py | 14 +++++++-------
 3 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index 55b8198..eadf0ca 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -38,4 +38,5 @@
 0.7
 - Added README
 - Expressions between quotes aren't parsed anymore
-- When adding a relation, the file must be choosen 1st, and then the default relation's name is the same as the filename
\ No newline at end of file
+- When adding a relation, the file must be choosen 1st, and then the default relation's name is the same as the filename
+- Changed internal rename method. Now uses a dictionary
\ No newline at end of file
diff --git a/parser.py b/parser.py
index 7e2f11b..0e163e9 100644
--- a/parser.py
+++ b/parser.py
@@ -106,8 +106,8 @@ def parse(expr):
 			res="%s.selection(\"%s\")" % (internal,parameters)
 			expr= ("%s%s%s") % (expr[0:start-2],res,expr[end+1:])
 		elif symbol=="ρ": #Rename
-			params=parameters.replace(",","\",\"").replace("➡","\",\"").replace(" ","")
-			res="%s.rename(\"%s\")" % (internal,params)
+			params=parameters.replace(",","\",\"").replace("➡","\":\"").replace(" ","")
+			res="%s.rename({\"%s\"})" % (internal,params)
 			expr= ("%s%s%s") % (expr[0:start-2],res,expr[end+1:])
 		else:
 			res="(%s)" % (internal)
diff --git a/relation.py b/relation.py
index 510090b..4497358 100644
--- a/relation.py
+++ b/relation.py
@@ -145,19 +145,19 @@ class relation (object):
 		
 		
 	
-	def rename(self,*params):
-		'''Operation rename. Takes an even number of parameters: (old,new,old,new....)
-		Will replace the 1st parameter with the 2nd, the 3rd with 4th, and so on...
+	def rename(self,params):
+		'''Operation rename. Takes a dictionatu
+		Will replace the itmem with its content.
+		For example if you want to rename a to b, provide {"a":"b"}
 		If an "old" field doesn't exist, None will be returned'''
 		result=[]
 		
 		newt=relation()
 		newt.header=header(list(self.header.attributes))
 		
-		for i in range(len(params)):
-			if i%2==0:
-				if (newt.header.rename(params[i],params[i+1])) == False:
-					return None
+		for i in params:
+			if (newt.header.rename(i,params[i])) == False:
+				return None
 		
 		newt.content=list(self.content)
 		return newt