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Hi Sir:
   I have some trouble in using sage tools to programming.  The trouble is:
When I insert a IfStatement using sage like insert the following statement:
     if (a == 1) { a = a + 1; a = a - 1;}
and when finishing insert, I unparse the DEP file and the output is very right.
But the trouble come, when I want to insert  another if after the if statement 
I insert just now, and unparse it,  but the output shows the second if statement
I inserted was inserted after the main statement.  when I insert the second If 
Statement, I am very sure that I insert the second if statement just after the 
first if statment, but the answer is not like this.  Would you tell there are
some problem when I insert the first if statement?  I say like this just because 
I can insert the if statement after another if statement if the if statement is
is originaly in the dep file.  So I think I have some wrong step in insert the
if statement.
   The program I insert the first if statement like this:
   (I insert the if statement before the statement *s):
   SgSymbol *a;
   SgVarRefExp *var;
   a = new SgVariableSymb("a",*SgTypeInt());
   var = new SgVarRefExp(*a);
   SgValueExp t(1);
   SgIfStmt *aif;
   SgStatement *truebody,themain;
   themain = f->mainProgram();  //f is : SgFile *f;
   truebody = NULL;
   aif = new SgIfStmt(SgEqOp(*var,t),*truebody);
   s->insertStmtBefore(*aif);  //s is the statement where the if statement should   insert before
   //the next is to insert the true body;
   SgStatement *first,*second;
   first = new SgCExpStmt(SgEqOp(*var,*var+t));
   second = new SgCExpStmt(SgEqOp(*var,*var-t));
   //up to here, the first if statement already inserted!
   //if I add another if statement like follow
   //then the second if statement is not follow the first statement but follow the main statement!
   //what is the matter???
   Thank you very much.
   I am very eager to get your hand!