diff -r 38782bff886a -r 6c38ca59927f SequenceableCollection.st
--- a/SequenceableCollection.st	Thu May 12 04:07:15 1994 +0200
+++ b/SequenceableCollection.st	Tue May 17 12:09:46 1994 +0200
@@ -26,7 +26,7 @@
 an index. SequenceableCollection is an abstract class - there are no
 instances of it in the system.
 
-$Header: /cvs/stx/stx/libbasic/SequenceableCollection.st,v 1.10 1994-03-30 09:41:04 claus Exp $
+$Header: /cvs/stx/stx/libbasic/SequenceableCollection.st,v 1.11 1994-05-17 10:08:55 claus Exp $
 
 written spring 89 by claus
 '!
@@ -98,6 +98,18 @@
      concrete implementations must define this"
 
     ^ self subclassResponsibility
+!
+
+keys
+    "return a collection with all keys in the Smalltalk dictionary"
+
+    |sz|
+
+    sz := self size.
+    sz == 0 ifTrue:[
+        ^ #()
+    ].
+    ^ 1 to:sz
 ! !
 
 !SequenceableCollection methodsFor:'comparing'!
@@ -1164,6 +1176,8 @@
      end           "{ Class: SmallInteger }"
      smallest thisOne|
 
+    "this is just a q&d hack - there must be better implementations for this ;-)"
+
     end := self size.
     1 to:end do:[:index |
         smallest := self at:index.
@@ -1184,9 +1198,9 @@
     ]
 
     "
-     #(1 16 7 98 3 19 4 0) topologicalSort:[:a :b | a < b]
-     #(1 16 7 98 3 19 4 0) sort:[:a :b | a < b]
-     Smalltalk allClasses asArray topologicalSort:[:a :b | b isSubclassOf:a]
+     #(1 16 7 98 3 19 4 0) topologicalSort:[:a :b | a < b]   Array(0 1 3 4 7 16 19 98)
+     #(1 16 7 98 3 19 4 0) sort:[:a :b | a < b]              Array(0 1 3 4 7 16 19 98)
+     Smalltalk allClasses asArray topologicalSort:[:a :b | b isSubclassOf:a] 
     "
 !
 
@@ -1272,6 +1286,9 @@
     1 to:stop do:[:index |
         aBlock value:(self at:index).
     ]
+    "
+     #(one two three four five six) do:[:element | Transcript showCr:element]
+    "
 !
 
 keysAndValuesDo:aTwoArgBlock
@@ -1284,6 +1301,26 @@
     1 to:stop do:[:index |
         aTwoArgBlock value:index value:(self at:index).
     ]
+    "
+     #(one two three four five six) keysAndValuesDo:[:key :element | Transcript show:key; space; showCr:element]
+    "
+!
+
+with:aSequenceableCollection do:aTwoArgBlock
+    "evaluate the argument, aBlock for successive elements from
+     each the receiver and the argument, aSequenceableCollection.
+     The second argument, aBlock must be a two-argument block.
+     The collection argument must implement access via a numeric key."
+
+    |stop  "{ Class: SmallInteger }" |
+
+    stop := self size.
+    1 to:stop do:[:index |
+        aTwoArgBlock value:(self at:index) value:(aSequenceableCollection at:index).
+    ]
+    "
+     #(one two three four five six) with:(1 to:10) do:[:el1 :el2 | Transcript show:el1; space; showCr:el2]
+    "
 !
 
 from:index1 to:index2 do:aBlock
@@ -1298,6 +1335,10 @@
     start to:stop do:[:index |
         aBlock value:(self at:index).
     ]
+
+    "
+     #(one two three four five six) from:3 to:5 do:[:element | Transcript showCr:element]
+    "
 !
 
 from:index1 to:index2 reverseDo:aBlock
@@ -1312,19 +1353,10 @@
     stop to:start by:-1 do:[:index |
         aBlock value:(self at:index).
     ]
-!
 
-with:aCollection do:aTwoArgBlock
-    "evaluate the argument, aBlock for successive elements from
-     each of the two collections self and aCollection.
-     aBlock must be a two-argument block"
-
-    |stop  "{ Class: SmallInteger }" |
-
-    stop := self size.
-    1 to:stop do:[:index |
-        aTwoArgBlock value:(self at:index) value:(aCollection at:index).
-    ]
+    "
+     #(one two three four five six) from:3 to:5 reverseDo:[:element | Transcript showCr:element]
+    "
 !
 
 reverseDo:aBlock
@@ -1337,6 +1369,9 @@
     sz to:1 by:-1 do:[:index |
         aBlock value:(self at:index).
     ]
+    "
+     #(one two three four five six) reverseDo:[:element | Transcript showCr:element]
+    "
 !
 
 collect:aBlock
@@ -1352,6 +1387,9 @@
         newCollection at:index put:(aBlock value:(self at:index)).
     ].
     ^ newCollection
+    "
+     #(one two three four five six) collect:[:element | element asUppercase]  
+    "
 !
 
 select:aBlock
@@ -1371,4 +1409,7 @@
         ].
     ].
     ^ newColl
+    "
+     #(one two three four five six) select:[:element | element startsWith:'f']   
+    "
 ! !