[plt-scheme] Understanding lambda

From: Grant Rettke (grettke at acm.org)
Date: Fri Feb 13 15:57:17 EST 2009

> As far as I know the concept of `consant' is not defined in scheme. But 1
> and 55 definitiley are (representations of) values (in fact self evaluating
> values, that is to say, the value of 55 is 55, whereas the value of say
> 'a-variable-name' can be anything from undefined to a very well defined
> value)

It is easier to say that "55 is 55", but in reality you have to take
into acount the evaluation model, and in consequence say that 55 is
self-evaluating because it is a core object type that is not a
procedure, and that when you type in 55 you really aren't typing 55 as
far as the interpreter is concerned you are just typing in the
external representation of 55. Did I get that right?

I didn't follow the HtDP or TSPL approach to learning Scheme initially
and I suspect it made the process more painful as a result.


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