ralt to meta trick

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+Lists
+--------
+Lists in haskell are homogenous: all elements must of the same type. They are
+linked lists, so cons-ing on the front is cheap and concatonating on the end
+can be expensive.
+
+Use ++ to concatonate two lists together:
+
+    ['a','b','c'] ++ ['d','e','f']
+
+Use : to cons (prepend) a single element:
+
+    0:[1,2,3,4,5,6]
+
+Use !! to pull out an element by index (zero indexed):
+
+    ['c','a','t'] !! 1
+
+Strings are lists of characters: "baby" is equivalent to ['b','a','b','y'],
+which is equivalent to 'b':'a':'b':'y':[]. The empty set is [] and is distinct
+from [[]].
+
+A couple functions help; 'head' is like 'car' and gives the first element,
+'tail' is like 'cdr' and gives everything except the first element, 'last'
+gives the last non-empty element, and 'init' gives everything except the
+'last'. 'length' gives the number of elements, 'null' is a test to see if this
+is the empty list, 
 
 Compilation
 ------------