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--- at:tutorial:appendix [2008/07/10 14:31] – * tvcutsem
+++ at:tutorial:appendix [2008/07/10 15:05] – * tvcutsem
@@ Line 102: / Line 102: @@
 ==== Vector ====
-A vector is a dynamically resizable AmbientTalk table (aka array). Vectors may be created as follows:
+A vector is a dynamically resizable AmbientTalk table (aka array). Indexed reading from and writing to a vector is fast (O(1)). Adding elements to a vector is mostly fast, but sometimes requires a resize of the vector. Vectors support the traditional stack operations ''push'' and ''pop'' and may be turned into sets by invoking their ''uniq'' method (note that a ''uniq''-ed vector is not permanently a Set: subsequent duplicates added to the vector will not be filtered).
+Vectors may be created as follows:
 <code>
@@ Line 125: / Line 127: @@
 // write idx'th element or raise IndexOutOfBounds exception
-//atPut(idx, val)
+atPut(idx, val)
 // iterate over the vector
@@ Line 148: / Line 150: @@
 select(start, stop)
-// appends an element to the back of the vector
+// appends an element to the back of the vector. Returns the vector itself
-// returns the vector itself
 add(element)
 // alias for add(element)
@@ Line 203: / Line 204: @@
 asTable()
 </code>
+The file ''at/collections/vector.at'' contains a unit tests that further helps to illustrate the usage of this Vector abstraction.
 ==== List ====
+The module ''/.at.collections.list'' implements Scheme-like list datastructures. The module exports the prototype ''NIL'', which is bound to the empty list. Non-empty lists are defined as a chain of cons-cells.
+The list module defines two styles to manipulate cons-cells: an object-oriented and a functional style. The object-oriented style represents cons-cells as ''Cons'' prototypes. Given a cons-cell ''c'', a new one can be constructed by invoking ''c.new(car, cdr)''. The car and cdr part of the cons-cell can be extracted by means of ''c.car'' and ''c.cdr''.
+The functional style allows one to manipulate lists by means of the following functions:
+<code>
+cons(car,cdr) -> a new cons-cell
+car(conscell) -> the car
+cdr(conscell) -> the cdr
+list(@items) -> a cons-cell representing the head of a list
+</code>
+Lists (cons-cells or the empty list) support the following operations:
+<code>
+// accessors for car and cdr
+car()
+cdr()
+// the length of the list
+length()
+// whether the list is empty or not
+isEmpty()
+// returns the nth element of the list
+nth(n)
+// apply a unary function to each element of the list
+each: fun
+// apply a function to each element and its index in the list
+// i.e. list.eachWithIndex: { |elt, idx| ... }
+eachWithIndex: fun
+// map a unary function over the list, returning a new list
+ map: fun
+// accumulate a value over a list
+inject: init into: accum
+// return a new list whose elements satisfy the unary predicate
+filter: cond
+// does the list contain the element?
+contains(elt, cmp := DEFAULTCOMPARATOR)
+// implode or join a list of text strings
+implode()
+join(txt)
+// drop the first n elements from the list
+tail(n)
+// prepend an element to the list
+add(elt)
+// insert an element in the list (functionally)
+insert(atPos, element)
+// return a new list where the element atPos is deleted
+delete(atPos)
+// functional append
+append(aList)
+// return the index of the first matching element, or nil if none is found
+find: filter
+// return the index in the list of the element or nil of not found
+indexOf(elt, cmp := DEFAULTCOMPARATOR)
+// return a list where the given element is removed
+remove(elt, cmp := DEFAULTCOMPARATOR)
+// return a new list where all objects for which filter(elt) is true are removed
+removeAll: filter
+// convert the list into a table
+asTable()
+</code>
+The file ''at/collections/list.at'' contains a unit test that further illustrates the usage of the list datastructure.