[Haskell-cafe] Haskell - string to list isusses, and more

Deniz Dogan deniz.a.m.dogan at gmail.com
Sun Jun 14 11:42:53 EDT 2009

2009/6/14 Gjuro Chensen <daimaox at gmail.com>:
> Hello everyone!
> Im a Haskell newbie, and Ive have few unanswered questions. For someone more
> experienced (at least I think so) its a very simple task, but I just cant
> get a grip on it and its pretty frustrating. It wouldn't be that bad if I
> haven't browse thru bunch of pages and tutorials and still nothing...
> The problem is: take a string, and if every words starts with uppercase
> letter then print yes, else no.
> Forum Text Bold -> yes
> Frog image File -> no
> Ive had my share of approaches to this, but I just cant make it work.
> Standard one seemed the most simple:
> search :: String -> String
> search [] = []
> and then use words (splits string on space) to split the string so I could
> get a list and go through it recursively. But how to apply words to entered
> string in this form?
> To find the first letter I came up with: first = take 1 (head x). And
> compare it with elem or ASCII values to determine if its upper case.
> Any help, advice or suggestion is appreciated.
> Thanks in advance!
> --
> View this message in context: http://www.nabble.com/Haskell---string-to-list-isusses%2C-and-more-tp24022673p24022673.html
> Sent from the Haskell - Haskell-Cafe mailing list archive at Nabble.com.
> _______________________________________________
> Haskell-Cafe mailing list
> Haskell-Cafe at haskell.org
> http://www.haskell.org/mailman/listinfo/haskell-cafe

As you say, there are a number of possible approaches to take here.
I'd say take a look at functions "all" [1] and "isUpper" [2], those
should be all you need.

* "all" takes a predicate (a function) and a list of elements. It
  returns True if that predicate holds for all of the elements in the
  list, otherwise False.

* "isUpper" takes a Char and returns True if that character is an
  uppercase letter, otherwise False.

[1] http://haskell.org/ghc/docs/latest/html/libraries/base/Prelude.html
[2] http://haskell.org/ghc/docs/latest/html/libraries/base/Data-Char.html

Deniz Dogan

More information about the Haskell-Cafe mailing list