MathGroup Archive 1999

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: ReplaceAll in If Statement

  • To: mathgroup at smc.vnet.net
  • Subject: [mg19459] Re: [mg19448] ReplaceAll in If Statement
  • From: Jean-Marie Thomas <jmt at agat.net>
  • Date: Sat, 28 Aug 1999 15:52:57 -0400
  • Organization: TeA
  • References: <199908250525.BAA24791@smc.vnet.net.>
  • Sender: owner-wri-mathgroup at wolfram.com

This happends because
a/.{opts} evaluates to {True} and not to True

Hope this helps,

jmt


On Wed, 25 Aug 1999, Tom Compton wrote:
> In the following sequence I expected z to evaluate to 1 in the
> Module.  It appears that the test in the module does not
> evaluate to either True or False.  I don't understand why.
> Can anyone explain?
> 
> In[1]:=
> opList={a->True};
> 
> In[2]:=
> test[opts___]:=Module[{},
> If[a /. {opts}, z=1, z=2, z=3];
> {a, z} /. {opts}]
> 
> In[3]:=
> test[opList]
> Out[3]=
> {{True,3}}
> 
> 
> 
> Tom Compton


  • Prev by Date: Re: Simple question about packages
  • Next by Date: Re: getting rid of TraditionalForm
  • Previous by thread: ReplaceAll in If Statement
  • Next by thread: Re: ReplaceAll in If Statement