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Using Switch with Words ??

 [1/8] from: tim::johnsons-web::com at: 31-Oct-2001 18:10

Hello All: Time to banish all questions about switches :>) Now I would like to use 'switch such that an argument is evaluated agains word values. Not being clear here... I know - so here is the example: x1: 1 ;treat as global x2: 2 x3: 3 switch-with-words: func[arg][ switch/default arg[ x1[print "equal to x1"] x2[print "equal to x2"] x3[print "equal to x3"] ][print "no case"] ] switch-with-words 3
>>no case
Oh fudge! I was hoping to see "equal to x3" Now how can I write 'switch-with-words to get equal to x3 as the result. Thanks again! -- Tim Johnson <[tim--johnsons-web--com]>

 [2/8] from: al:bri:xtra at: 1-Nov-2001 17:46

Instead of:
> switch/default arg[
use: switch/default arg reduce [ ; etcetera... Andrew Martin ICQ: 26227169

 [3/8] from: tim:johnsons-web at: 31-Oct-2001 20:51

On Thu, Nov 01, 2001 at 05:46:53PM +1300, Andrew Martin wrote:
> Instead of: > > switch/default arg[
<<quoted lines omitted: 3>>
> ICQ: 26227169 > -><-
Hi Martin: Egad! That does it. It's been a good day. :>) Thank you. Tim

 [4/8] from: al:bri:xtra at: 1-Nov-2001 19:32

While it's easy to think that: switch Value [ 1 [print "one"] 2 [print "two"] ] is just like C++'s (IIRC) : switch value { 1: cout << "1"; break; 2: cout << "2"; break; } the power of Rebol is in the ability to manipulate itself. Notice that 'switch is a function, and it's second parameter is a block, so this works: Switch-Block: [ 1 [print "one"] 2 [print "two"] ] switch Value Switch-Block and then you can easily see how one can 'compose, 'load, 'do or 'reduce Switch-Block to create interesting effects. Andrew Martin ICQ: 26227169

 [5/8] from: matt:fitzgerald:bigpond at: 1-Nov-2001 17:54

C++: switch(value) { case 1 : cout << value << endl; break; case 2 : cout << value << endl; break; default : cout << value << endl; } Oh well.. not Rebol, but a bit different to what you had. -Matt

 [6/8] from: al:bri:xtra at: 1-Nov-2001 20:57

Matt wrote:
> C++:
How quickly I forget... Andrew Martin With Rebol, you don't have to worry about silly sintax... :-) ICQ: 26227169

 [7/8] from: joel:neely:fedex at: 1-Nov-2001 5:31

Hi, Matt, Matt Fitzgerald wrote:
> switch(value) { > case 1 :
<<quoted lines omitted: 6>>
> cout << value << endl; > }
Given that the same thing can be coded in C as printf "%d\n", value; it's easy to see what an improvement C++ is... ;-) -jn- -- ; sub REBOL {}; sub head ($) {@_[0]} REBOL [] # despam: func [e] [replace replace/all e ":" "." "#" "@"] ; sub despam {my ($e) = @_; $e =~ tr/:#/.@/; return "\n$e"} print head reverse despam "moc:xedef#yleen:leoj" ;

 [8/8] from: tim:johnsons-web at: 1-Nov-2001 7:49

On Thu, Nov 01, 2001 at 07:32:24PM +1300, Andrew Martin wrote: ..........
> and then you can easily see how one can 'compose, 'load, 'do or 'reduce > Switch-Block to create interesting effects. > -><-
One of my obstacles to learning rebol has been that since I've written in C for 12 years, I find "C-thinking" getting in the way. What this conversation about switches has taught me is to think of 'switch as a function, the cases block as an 'argument'. The tendency of a C programmer is to think of switch as a control structure (such as I was). Good thread!
> > -- > To unsubscribe from this list, please send an email to > [rebol-request--rebol--com] with "unsubscribe" in the > subject, without the quotes.
-- Tim Johnson <[tim--johnsons-web--com]>

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