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[REBOL] solved: another question about contexts and layouts

From: mh983::yahoo::com at: 12-Mar-2002 11:18

Woo hoo! I've discovered my problem (I think), and as usual, it's pretty dumb. The following example is essentially the same as the first, but removes some fluff and removes 'layout from the equation. The problem is that inner-ctx is just a block and is not turned into an object at the time we call "context outer-ctx". Therefore, both obj1 and obj2 refer to the same inner-ctx block. Since obj2 is created last, the value bound to 'name in the inner-ctx block will be Two , and both obj1 and obj2 will refer to it. The simple solution is to just include copy/deep for the inner-ctx. I have a hard time making sense of this concept and would appreciate it greatly if someone has a clear description. Is it that since the series is identical, REBOL just points all instances to the same memory location? For instance, in java if you write: String x = "hello"; String y = "hello"; You are actually pointing to the same String object in memory. But since Strings are immutable, you don't get a surprise change to y when you change x. I'm wondering if it's the same concept in REBOL except the series is not immutable. Anyway, thanks for listening. Here's the new example if anyone's interested: REBOL[] outer-ctx: [ name: "unnamed" myinner: none inner-ctx: [ emit: does [print ["name is" name]] ] init: does [ myinner: context inner-ctx ] ] ; create object1 and give it a name obj1: context outer-ctx obj1/name: "One" ; create object2 and give it name obj2: context outer-ctx obj2/name: "Two" obj1/init print obj1/name ; prints "One" obj1/myinner/emit ; print "Two"