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Re: Add syntax highlighting to own command

• To: mathgroup at smc.vnet.net
• Subject: [mg101783] Re: Add syntax highlighting to own command
• From: Daniel <janzon at gmail.com>
• Date: Fri, 17 Jul 2009 05:02:13 -0400 (EDT)
• References: <200907090600.CAA17547@smc.vnet.net> <h3766u$f9h$1@smc.vnet.net>

Hi Bastian,

I think the line

>   Let[ { head_ }, expr_ ] := With[ { head }, expr ]

is unnecessary since tail_ can match the empty sequence in

>   Let[ { head_, tail__ }, expr_ ] :=
>     With[ { head }, Let[ { tail }, expr ] ]

Or did I miss something?

All the best,
Daniel


On 16 Juli, 14:19, earth... at web.de (Bastian Erdnuess) wrote:
> Bastian Erdnuess <earth... at web.de> wrote:
> > PS: Has somebody a hint how to get
>
> >   lhs := Let[ vars, expr /; cond ]
>
> > to work?
>
> I got it:
>
>   Let /: ( lhs_ := Let[ vars_, expr_ /; cond_ ] ) :=
>     Let[ vars, lhs := expr /; cond ]
>
> My whole Let looks now like
>
>   SetAttributes[ Let, HoldAll ]
>   SyntaxInformation[ Let ] =
>     { "ArgumentsPattern" -> { _, _ } }
>
>   Let /: ( lhs_ := Let[ vars_, expr_ /; cond_ ] ) :=
>     Let[ vars, lhs := expr /; cond ]
>   Let[ { }, expr_ ] := expr;
>   Let[ { head_ }, expr_ ] := With[ { head }, expr ]
>   Let[ { head_, tail__ }, expr_ ] :=
>     With[ { head }, Let[ { tail }, expr ] ]
>
> It looks like it doesn't matter in which order I give the rules.
> Mathematica applies always the most specific.  How does it know?
>
> Bastian

• References:
  • Add syntax highlighting to own command
    • From: earthnut@web.de (Bastian Erdnuess)