--- a/SequenceableCollection.st	Mon Feb 03 01:48:41 2020 +0100
+++ b/SequenceableCollection.st	Mon Feb 03 02:34:03 2020 +0100
@@ -440,6 +440,8 @@
     ^ self == SequenceableCollection
 ! !
 
+
+
 !SequenceableCollection methodsFor:'Compatibility-Squeak'!
 
 allButFirst
@@ -738,6 +740,7 @@
     ^ self replaceFrom:start to:stop with:anArray startingAt:repStart
 ! !
 
+
 !SequenceableCollection methodsFor:'accessing'!
 
 after:anObject
@@ -3613,6 +3616,18 @@
     "Modified (comment): / 16-11-2016 / 21:35:36 / cg"
 !
 
+copyReplaceAllForWhich:checkBlock with:newElement
+    "return a copy of the receiver, where all elements for which checkBlock
+     returns true will are replaced by newElement."
+
+    ^ (self copyFrom:1) replaceAllForWhich:checkBlock with:newElement
+
+    "
+     #(1 2 1 3 4 5 1 2 1 2) copyReplaceAllForWhich:[:e | e > 2] with:99
+     'hello 1234 world' copyReplaceAllForWhich:#isDigit with:$*
+    "
+!
+
 copyReplaceAllSubcollections:subColl with:newColl
     "return a copy of the receiver, with all sequences of subColl replaced
      by newColl (i.e. slice in the newColl in place of the subColl)."
@@ -8032,6 +8047,7 @@
     "Created: 14.2.1997 / 16:13:03 / cg"
 ! !
 
+
 !SequenceableCollection methodsFor:'searching'!
 
 asMapAt:key ifAbsent:exceptionValue