<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; charset=iso-8859-1"> <META content="MSHTML 6.00.6000.16809" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=#ffffff> <DIV><FONT face="Courier New" size=2>Try:</FONT></DIV> <DIV><FONT face="Courier New" size=2>(define a 'a-symbol)</FONT></DIV> <DIV><FONT face="Courier New" size=2>(set! a 300)</FONT></DIV> <DIV><FONT face="Courier New" size=2>Jos</FONT></DIV> <BLOCKQUOTE style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> <DIV style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B> <A title=adityashukla1983@gmail.com href="mailto:adityashukla1983@gmail.com">aditya shukla</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A title=grettke@acm.org href="mailto:grettke@acm.org">Grant Rettke</A> </DIV> <DIV style="FONT: 10pt arial"><B>Cc:</B> <A title=plt-edu@list.cs.brown.edu href="mailto:plt-edu@list.cs.brown.edu">plt edu</A> ; <A title=plt-scheme@list.cs.brown.edu href="mailto:plt-scheme@list.cs.brown.edu">PLT Scheme ML</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, February 18, 2009 7:52 PM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [plt-scheme] Defining structures</DIV> <DIV><BR></DIV>A question that comes to mind if variables in scheme do not have type in scheme thus can be say that<BR><BR>(define a 9) -here a is a placeholder for a value whose tag is a number<BR><BR>> (define a 'aditya)<BR>define: cannot redefine name: a<BR><BR><BR><BR>why can't we redefine a here?<BR><BR><BR>Aditya<BR><BR><BR> <P> <HR> <P></P>_________________________________________________<BR>  For list-related administrative tasks:<BR>  <A href="http://list.cs.brown.edu/mailman/listinfo/plt-scheme">http://list.cs.brown.edu/mailman/listinfo/plt-scheme</A><BR></BLOCKQUOTE></BODY></HTML>