[Haskell-beginners] substitution

Yitzchak Gale gale at sefer.org
Mon Mar 1 17:59:29 EST 2010

John Moore wrote:
> Can anyone explain what I'm doing wrong in the subtitution of the Let
> statement.

Look more carefully at the "right" case for "evalStep..Let".
The result should still have a Let in it - since e1 is not
a value yet, you're not ready yet to do the substitution.

Hope this helps,

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