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Re: perplexed by blank sequence in pattern replacement


Hi,

try

Replace[a*b*c, Verbatim[Times][mysequence__] :> {mysequence}]

and you got what you expect.
Regards
   Jens

Blake wrote:
> Dear MathGroup:
> 
> I have been blithely using blank sequences in pattern matching for some
> time. In persuit of a bug in a package of mine, I was quite alarmed to
> find that I don't really understand how to use the blank sequence, as
> expressed in the following simplified example:
> 
> In[1]:=Replace[a*b*c,Times[mysequence__]:>{mysequence}]
> 
> Out[1]={a b c}
> 
> I expected Out[1]={a,b,c}, from a naieve reading of the full form of
> a*b*c
> 
> In[2]:=FullForm[a*b*c]
> 
> Out[2]//FullForm=Times[a,b,c]
> 
> Will someone PLEASE tell me why In[1] does not yield the results I
> expected? (I can readily use a work-around, what I am concerned with is
> a correct understanding of pattern matching).
> 
> Blake Laing
> thesis slave
> University of Oklahoma
> 


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