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[REBOL] Re: make <object-type> append

From: gjones05:mail:orion at: 14-Jun-2001 8:37

From: "Joel Neely"
> Forgive me if I insult your intelligence by > proceeding in very small steps; that's just > my own style for picking apart the pieces > of a puzzle with several components, so > it's about me and not about you.
Hi, Joel, One has to have intelligence, in order for the intelligence to be insulted! ;-) The stepwise approach serves as a type of assertion checking for erroneous assumptions. If PeKr had not beat you to the Send key, your explanation would have guaranteed that I understood. Thanks for taking the time. Just a couple more comments for your edification... ...
> I have no idea *why* one would APPEND two literal blocks before > supplying them as a spec for MAKE (instead of simply writing > their content as a single block), but I hope the above makes > it more clear *what* is happening:
Yes, it does. I left out the context in which RT uses this method, but I'll explain further below. ...
> AFAICT, you can use any expression that constructs a correctly- > formed block to supply the second (spec) argument to MAKE. e.g.:
For some reason I developed a mental block (a stuttering paradigm shift?). I had it in my head that this construct was some special form of make!, forgetting that append is just passing along the second parameter (the spcification, in this case). Like I said to PeKr, it is embarrassingly obvious now. I am always glad to learn, so it was worth it. ...
> That just happens to be a particularly awkward way to do it! ;-)
The context in which RT used this construct was to conditionally pass another specification to the make. Here is the snippet: HTTP-Get-Header: make HTTP-Get-Header append [ Referer: either find port/url #"?" [head clear find copy port/url #"?"] [port/url] Content-Type: "application/x-www-form-urlencoded" Content-Length: length? post-data/2 ] either block? post-data/3 [post-data/3] [[]] This was slightly shorter than using a second conditional make, like: HTTP-Get-Header: make HTTP-Get-Header [ Referer: either find port/url #"?" [head clear find copy port/url #"?"] [port/url] Content-Type: "application/x-www-form-urlencoded" Content-Length: length? post-data/2 ] if block? post-data/3 [ HTTP-Get-Header: make HTTP-Get-Header [ post-data/3 ] I guess I am still getting used to the functional aspect of functional programming. It is happening less often. Thanks again for the thorough discussion. --Scott Jones