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</o:shapelayout></xml><![endif]--></head><body lang=ES link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Greetings Olav,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>I don’t understand why you try to math using that kind pattern, you can use the common way.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Instead of using ([0,1,2] ++ _) = [0,1,2,3,4] you can use [0,1,2| _] = [0,1,2,3,4] pattern matching.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Best,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'>Ivan.<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri","sans-serif";color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'>De:</span></b><span style='font-size:10.0pt;font-family:"Tahoma","sans-serif"'> erlang-questions-bounces@erlang.org [mailto:erlang-questions-bounces@erlang.org] <b>En nombre de </b>Olav Frengstad<br><b>Enviado el:</b> miércoles, 17 de abril de 2013 16:27<br><b>Para:</b> erlang-questions@erlang.org Questions<br><b>Asunto:</b> [erlang-questions] Wildcard matching a list of strings vs atoms/binaries<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hey,<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>I'm getting some unexpected behavior when trying to pattern match the head of a list.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>When matching against a list of integers I can successfully do a wildcard match:<o:p></o:p></p></div><div><p class=MsoNormal>27> ("ab ++ _) = "abcd".<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>But when trying to do the same with a list of atoms i get the error: * 1: illegal pattern:<o:p></o:p></p></div><div><div><p class=MsoNormal>28> ([a,b,c] ++ _) = [a,b,c,d].<o:p></o:p></p></div><div><p class=MsoNormal>* 1: illegal pattern<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>So just making sure there's no magic in string matching i also try with an actual list of integers:<o:p></o:p></p></div></div><div><div><p class=MsoNormal>29> ([0,1,2] ++ _) = [0,1,2,3,4]. <o:p></o:p></p></div><div><p class=MsoNormal>[0,1,2,3,4]<o:p></o:p></p></div></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Why can't I pattern match a lists with other values integers?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>What i'm looking to achieve is to provide wildcard matching on a gen_event handler so I can do matches like this:<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>handle_event((Match ++ _), State#state{match = Match}) -><o:p></o:p></p></div><div><p class=MsoNormal>% handle<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Any other alternatives is appreciated, current implementation uses lists:suffix/2<o:p></o:p></p></div><div><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal>-- <br>Med Vennlig Hilsen<o:p></o:p></p><div><p class=MsoNormal>Olav Frengstad<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Systemutvikler // FWT<o:p></o:p></p></div><div><p class=MsoNormal>+47 920 42 090<o:p></o:p></p></div></div></div></div></body></html>