Merge pull request coffeescript-cookbook#37 from fhemberger/master

Various updates

Author: peterhellberg

chapters/arrays/max-array-value.md

@@ -9,22 +9,20 @@ You need to find the largest value contained in an array.
 
 ## Solution
 
-In ECMAScript 5, use `Array#reduce`. In older javascripts, use Math.max over a list comprehension:
+In ECMAScript 5, use `Array#reduce`. In older javascripts, use Math.max:
 
 {% highlight coffeescript %}
 # ECMAScript 5
 [12,32,11,67,1,3].reduce (a,b) -> Math.max a, b
 # => 67
 
 # Pre-EC5
-max = Math.max(max or= num, num) for num in [12,32,11,67,1,3]
+max = Math.max.apply(null, [12,32,11,67,1,3])
 # => [ 12, 32, 32, 67, 67, 67 ]
 max
 # => 67
 {% endhighlight %}
 
 ## Discussion
 
-`Math.max` compares two numbers and returns the larger of the two; the rest of this recipe (both versions) is just iterating over the array to find the largest one. It is interesting to note that when assigning from a list comprehension, the last item evaluated will be returned to the assignment but the expression itself (such as in the node.js coffeescript interpreter) evaluates to the list comprehension's complete mapping. This means that the Pre-EC5 version will duplicate the array.
-
-For very large arrays in ECMAScript 4, a more memory efficient approach might be to initialize `max` to the first element of the array, and then loop over it with a traditional for loop. Since non-idiomatic CoffeeScript is discouraged in the Cookbook, this approach is left as an exercise to the reader.
+`Math.max` compares two numbers and returns the larger of the two; the rest of this recipe (both versions) is just iterating over the array to find the largest one.

chapters/strings/trimming-whitespace-from-a-string.md

@@ -34,13 +34,12 @@ To trim only trailing whitespace, use the following:
 
 ## Discussion
 
-Opera, Firefox and Chrome all have a native string prototype `trim` method, and the other browsers could add one as well. For this particular method, I would use the built-in method where possible:
+Opera, Firefox and Chrome all have a native string prototype `trim` method, and the other browsers could add one as well. For this particular method, I would use the built-in method where possible, otherwise create a polyfill:
 
 {% highlight coffeescript %}
-trim = (val) ->
-  if String::trim? then val.trim() else val.replace /^\s+|\s+$/g, ""
+if !String::trim? then String::trim = -> @replace /^\s+|\s+$/g, ""
 
-trim "  padded string  "
+"  padded string  ".trim
 # => 'padded string'
 {% endhighlight %}