Re: Question concerning MakeBoxes

*To*: mathgroup at smc.vnet.net*Subject*: [mg60390] Re: [mg60378] Question concerning MakeBoxes*From*: "David Park" <djmp at earthlink.net>*Date*: Thu, 15 Sep 2005 05:16:12 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

Carlos, First, on Version 5.2 I have no problem with repeated evaluation. The TraditionalForm output always uses the new formatting. Second, by using the following definition, it is possible to copy and paste the output. Unprotect[And]; And /: MakeBoxes[And[c__], TraditionalForm] := (InterpretationBox[#1, #2] &) @@ {RowBox[{"\[And]", RowBox[{StyleBox["{", SpanMaxSize -> \[Infinity]], GridBox[({#1} &) /@ (MakeBoxes[#1, TraditionalForm] &) /@ {c}, ColumnAlignments -> {Left}], StyleBox["}", ShowContents -> False]}], " "}], And[c]}; Protect[And]; Using the pure function form of InterpretationBox allows the arguments to be evaluated. Last, when I used the above on Version 5.0.1 and on 5.1.1 I again had no trouble with repeated evaluation so I wonder if there is some setting on your system that has gotten changed. David Park djmp at earthlink.net http://home.earthlink.net/~djmp/ From: Cca [mailto:cca at gregosetroianos.mat.br] To: mathgroup at smc.vnet.net Let's start a new Mathematica (5.1) session and note that FormatValues[And] is the empty list. I want to define a rule for formatting logical conjunctions and disjunctionsin in such a way that, for example, the conjunction p&&q&&r is formatted in TraditionalForm as RowBox[{"\[And]", RowBox[{StyleBox["{",SpanMaxSize->\[Infinity]], GridBox[{{"p"},{"q"},{"r"}},ColumnAlignments->{Left}], StyleBox["}",ShowContents->False]}]," "}]//DisplayForm (As far as I know, the idea for this interesting and convenient "grid notation" is due to Bruno BuchBerger, but this is another history.) For me, one obvious solution to this problem should be something like Unprotect[And]; And/:MakeBoxes[And[c__],TraditionalForm]:= RowBox[{"\[And]", RowBox[{StyleBox["{",SpanMaxSize->\[Infinity]], GridBox[{#}&/@(MakeBoxes[#,TraditionalForm]&/@{c}), ColumnAlignments->{Left}], StyleBox["}",ShowContents->False]}]," "}]; Protect[And]; In fact, p&&q&&r//TraditionalForm is now displayed as intended. However, it works only once: evaluating again p&&q&&r//TraditionalForm gives the built-in traditional formatting. After inspecting FormatValues[And] we see what is going on: my formatting rule is the LAST on the list. So, in order to force Mathematica to apply my definition first, I evaluate Unprotect[And]; FormatValues[And]=Reverse@FormatValues[And]; Protect[And]; This solves my problem, but in a somewhat inelegant way. My questions are: (1) what is the explanation for this behavior? (2) how can I get the intended result without reversing FormatValues[And]? My anticipated thanks for any help. Carlos César de Araújo Gregos & Troianos Educacional www.gregosetroianos.mat.br Belo Horizonte, MG, Brazil (31) 3283-1122