Re: "Programming With Mathematica" Exercise help

*To*: mathgroup at smc.vnet.net*Subject*: [mg130471] Re: "Programming With Mathematica" Exercise help*From*: plank.in.sequim at gmail.com*Date*: Sat, 13 Apr 2013 20:36:34 -0400 (EDT)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*Delivered-to*: l-mathgroup@wolfram.com*Delivered-to*: mathgroup-newout@smc.vnet.net*Delivered-to*: mathgroup-newsend@smc.vnet.net*References*: <kk5r6r$ric$1@smc.vnet.net> <kkasd1$ril$1@smc.vnet.net>

> In order to block evaluation during input use "Unevaluated" > > z = 11; > a = 9; > Unevaluated[z + 3] /. z -> a This seems closest in spirit to what I thought the answer was meant to be. I had to put a HoldPattern on the z in the right half of the substitution or it would evaluate to 11 and so end up as 11->a. Nice, though, because it didn't require the ReleaseHold.