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Conditional SetDelayed with Replacement

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  • Subject: [mg92790] Conditional SetDelayed with Replacement
  • From: Raffy <raffy at>
  • Date: Mon, 13 Oct 2008 06:20:01 -0400 (EDT)

I've been having difficulty getting the following code to work as

Do[f[x_ /; x < i^2] = i, {i, 5}];

The problem should be obvious: the i^2 is not be evaluated (since its
held by SetDelayed).

The only solution I've found thus far, has been doing the following:

(f[x_ /; x < #^2] = #)& /@ Range[5]
Do[(f[x_ /; x < #^2] = #)&[i], {i, 5}];

What kind of Hold, ReleaseHold, Evalulate, or Pattern Replacement
would be needed to get the first example working without using a pure-
function for replacement?

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