Programación en Ada/Unidades predefinidas/Ada.Strings.Fixed
Ada.Strings.Fixed proporciona subprogramas para la transformación y el manejo de strings de tamaño fijo.
Ejemplo Editar
package Fechas is type Fecha is record Dia : Positive range 1 .. 31; Mes : Positive range 1 .. 12; Año : Positive range 1 .. 3000; end record; subtype String_Fecha is String (1..10); -- Pasa la fecha a string en formato "dd-mm-aaaa". -- function Imagen (F: Fecha) return String_Fecha; end Fechas;
with Ada.Strings.Fixed; use Ada.Strings.Fixed; use Ada.Strings; package body Fechas is function Imagen (F: Fecha) return String_fecha is procedure Mover_Imagen_Positive (N: Positive; S: in out String) is begin -- Move copia un string en otro de otro tamaño, añadiendo un -- padding opcionalmente. Trim elimina los blancos a izquierda o -- derecha (en este caso el blanco que pone el 'Image). Move (Source => Trim (Positive'Image (N), Left), Target => S, Justify => Right, Pad => '0'); end Mover_Imagen_Positive; S_Fecha : String_Fecha; begin Mover_Imagen_Positive (F.Dia, S_Fecha (1..2)); S_Fecha (3) := '-'; Mover_Imagen_Positive (F.Mes, S_Fecha (4..5)); S_Fecha (6) := '-'; Mover_Imagen_Positive (F.Año, S_Fecha (7..10)); return S_Fecha; end Imagen; end Fechas;
Especificación Editar
Según el manual de referencia, la especificación de este paquete ha de ser la siguiente:
with Ada.Strings.Maps; package Ada.Strings.Fixed is pragma Preelaborate(Fixed); -- "Copy" procedure for strings of possibly different lengths procedure Move (Source : in String; Target : out String; Drop : in Truncation := Error; Justify : in Alignment := Left; Pad : in Character := Space); -- Search subprograms function Index (Source : in String; Pattern : in String; Going : in Direction := Forward; Mapping : in Maps.Character_Mapping := Maps.Identity) return Natural; function Index (Source : in String; Pattern : in String; Going : in Direction := Forward; Mapping : in Maps.Character_Mapping_Function) return Natural; function Index (Source : in String; Set : in Maps.Character_Set; Test : in Membership := Inside; Going : in Direction := Forward) return Natural; function Index_Non_Blank (Source : in String; Going : in Direction := Forward) return Natural; function Count (Source : in String; Pattern : in String; Mapping : in Maps.Character_Mapping := Maps.Identity) return Natural; function Count (Source : in String; Pattern : in String; Mapping : in Maps.Character_Mapping_Function) return Natural; function Count (Source : in String; Set : in Maps.Character_Set) return Natural; procedure Find_Token (Source : in String; Set : in Maps.Character_Set; Test : in Membership; First : out Positive; Last : out Natural); -- String translation subprograms function Translate (Source : in String; Mapping : in Maps.Character_Mapping) return String; procedure Translate (Source : in out String; Mapping : in Maps.Character_Mapping); function Translate (Source : in String; Mapping : in Maps.Character_Mapping_Function) return String; procedure Translate (Source : in out String; Mapping : in Maps.Character_Mapping_Function); -- String transformation subprograms function Replace_Slice (Source : in String; Low : in Positive; High : in Natural; By : in String) return String; procedure Replace_Slice (Source : in out String; Low : in Positive; High : in Natural; By : in String; Drop : in Truncation := Error; Justify : in Alignment := Left; Pad : in Character := Space); function Insert (Source : in String; Before : in Positive; New_Item : in String) return String; procedure Insert (Source : in out String; Before : in Positive; New_Item : in String; Drop : in Truncation := Error); function Overwrite (Source : in String; Position : in Positive; New_Item : in String) return String; procedure Overwrite (Source : in out String; Position : in Positive; New_Item : in String; Drop : in Truncation := Right); function Delete (Source : in String; From : in Positive; Through : in Natural) return String; procedure Delete (Source : in out String; From : in Positive; Through : in Natural; Justify : in Alignment := Left; Pad : in Character := Space); -- String selector subprograms function Trim (Source : in String; Side : in Trim_End) return String; procedure Trim (Source : in out String; Side : in Trim_End; Justify : in Alignment := Left; Pad : in Character := Space); function Trim (Source : in String; Left : in Maps.Character_Set; Right : in Maps.Character_Set) return String; procedure Trim (Source : in out String; Left : in Maps.Character_Set; Right : in Maps.Character_Set; Justify : in Alignment := Strings.Left; Pad : in Character := Space); function Head (Source : in String; Count : in Natural; Pad : in Character := Space) return String; procedure Head (Source : in out String; Count : in Natural; Justify : in Alignment := Left; Pad : in Character := Space); function Tail (Source : in String; Count : in Natural; Pad : in Character := Space) return String; procedure Tail (Source : in out String; Count : in Natural; Justify : in Alignment := Left; Pad : in Character := Space); -- String constructor functions function "*" (Left : in Natural; Right : in Character) return String; function "*" (Left : in Natural; Right : in String) return String; end Ada.Strings.Fixed;