Talk:Erlang Programming/Expressions

The problems are somewhat confusing:
 * 1) Write an expression that matches the pattern H2 to the reverse of the list [{1,2},{2,1}].
 * 2) Write an expression that matches the pattern H3 to the length of the list [{1,2},{2,1}].
 * 3) Write an expression that matches the pattern H4 to the length of the flattened version of the list [{1,2},{2,1}].

Problem #1 is easy enough, that information is given in the article.

Problem #2 doesn't say whether they should be counted, or if the  should be used. If it's the former, I don't yet have enough information to know how to do this as a reader. If it's the latter, I haven't been introduced to the  function. It doesn't appear to be part of the lists module, either.

Problem #3 doesn't describe what is intended by 'flattened version'. Perhaps example output would be good.