File : strings-utils.ads


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--  $Id: strings-utils.ads,v 1.3 2004/01/21 21:05:36 Jano Exp $


-- Utility functions for strings


with Strings.Fields;

package Strings.Utils is

   Illegal_character : Exception;

   type Indexes is record
      First, Last : Positive;
   end record;

   type Index_array is array (Positive range <>) of Indexes;

   -- Makes everything outside 'a' .. 'z', '0' .. '9' a blank

   -- Converts the string to lowercase and basic character mapping

   -- Preserves "-" for negative queries.

   -- Resulting string has no more of a consecutive space

   function Simplify (S : in String) return String;

   -- Removes -" " members in a string (must have quotes).

   function Positivize (S : in String) return String;

   -- Returns Indexes for all words inside a string, with a minimum length.

   -- String must be simplified or wrong results can occur

   function Tokenize (S : in String; Min_len : Positive := 3) 
      return Index_array;

   -- These return "" if nothing to be returned

   function Head (S : in String; Separator : in Character := ' ') 
      return String;
   function Tail (S : in String; Separator : in Character := ' ')
      return String;

   -- Trim a string from spaces

   function Trim (S : in String) return String;

   -- Replace all occurrences of a string by another:

   function Replace (
      Source : in String; Pattern : in String; By : in String) return String;

   -- return the nth enclosed field:

   function Select_field (
      S     : in String;
      Open  : in Character;
      Close : in Character;
      Pos   : in Positive := 1) return String;

end Strings.Utils;