Curso de Ada - Paquete Ada.Strings.Fixed

Ejemplo

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

Según el manual de referencia de Ada∞, 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;

Manual de refencia de Ada

• A.4.3 Fixed-Length String Handling∞