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G.1.3 Complex Input-Output

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The generic package Text_IO.Complex_IO defines procedures for the formatted input and output of complex values. The generic actual parameter in an instantiation of Text_IO.Complex_IO is an instance of Numerics.Generic_Complex_Types for some floating point subtype. Exceptional conditions are reported by raising the appropriate exception defined in Text_IO. 

Static Semantics

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The generic library package Text_IO.Complex_IO has the following declaration: 
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with Ada.Numerics.Generic_Complex_Types;
generic
   with package Complex_Types is
         new Ada.Numerics.Generic_Complex_Types (<>);
package Ada.Text_IO.Complex_IO is
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   use Complex_Types;
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   Default_Fore : Field := 2;
   Default_Aft  : Field := Real'Digits - 1;
   Default_Exp  : Field := 3;
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   procedure Get (File  : in  File_Type;
                  Item  : out Complex;
                  Width : in  Field := 0);
   procedure Get (Item  : out Complex;
                  Width : in  Field := 0);
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   procedure Put (File : in File_Type;
                  Item : in Complex;
                  Fore : in Field := Default_Fore;
                  Aft  : in Field := Default_Aft;
                  Exp  : in Field := Default_Exp);
   procedure Put (Item : in Complex;
                  Fore : in Field := Default_Fore;
                  Aft  : in Field := Default_Aft;
                  Exp  : in Field := Default_Exp);
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   procedure Get (From : in  String;
                  Item : out Complex;
                  Last : out Positive);
   procedure Put (To   : out String;
                  Item : in  Complex;
                  Aft  : in  Field := Default_Aft;
                  Exp  : in  Field := Default_Exp);
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end Ada.Text_IO.Complex_IO;
9.1/2
  The library package Complex_Text_IO defines the same subprograms as Text_IO.Complex_IO, except that the predefined type Float is systematically substituted for Real, and the type Numerics.Complex_Types.Complex is systematically substituted for Complex throughout. Non-generic equivalents of Text_IO.Complex_IO corresponding to each of the other predefined floating point types are defined similarly, with the names Short_Complex_Text_IO, Long_Complex_Text_IO, etc. 
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The semantics of the Get and Put procedures are as follows: 
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procedure Get (File  : in  File_Type;
               Item  : out Complex;
               Width : in  Field := 0);
procedure Get (Item  : out Complex;
               Width : in  Field := 0);
12/1
The input sequence is a pair of optionally signed real literals representing the real and imaginary components of a complex value These components have the format defined for the corresponding Get procedure of an instance of Text_IO.Float_IO (see A.10.9) for the base subtype of Complex_Types.Real. The pair of components may be separated by a comma or surrounded by a pair of parentheses or both. Blanks are freely allowed before each of the components and before the parentheses and comma, if either is used. If the value of the parameter Width is zero, then 
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15.1
If a nonzero value of Width is supplied, then
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Returns, in the parameter Item, the value of type Complex that corresponds to the input sequence.
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The exception Text_IO.Data_Error is raised if the input sequence does not have the required syntax or if the components of the complex value obtained are not of the base subtype of Complex_Types.Real.
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procedure Put (File : in File_Type;
               Item : in Complex;
               Fore : in Field := Default_Fore;
               Aft  : in Field := Default_Aft;
               Exp  : in Field := Default_Exp);
procedure Put (Item : in Complex;
               Fore : in Field := Default_Fore;
               Aft  : in Field := Default_Aft;
               Exp  : in Field := Default_Exp);
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Outputs the value of the parameter Item as a pair of decimal literals representing the real and imaginary components of the complex value, using the syntax of an aggregate. More specifically,
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procedure Get (From : in  String;
               Item : out Complex;
               Last : out Positive);
28/2
Reads a complex value from the beginning of the given string, following the same rule as the Get procedure that reads a complex value from a file, but treating the end of the string as a file terminator. Returns, in the parameter Item, the value of type Complex that corresponds to the input sequence. Returns in Last the index value such that From(Last) is the last character read.
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The exception Text_IO.Data_Error is raised if the input sequence does not have the required syntax or if the components of the complex value obtained are not of the base subtype of Complex_Types.Real.
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procedure Put (To   : out String;
               Item : in  Complex;
               Aft  : in  Field := Default_Aft;
               Exp  : in  Field := Default_Exp);
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Outputs the value of the parameter Item to the given string as a pair of decimal literals representing the real and imaginary components of the complex value, using the syntax of an aggregate. More specifically, 
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The exception Text_IO.Layout_Error is raised if the given string is too short to hold the formatted output. 

Implementation Permissions

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Other exceptions declared (by renaming) in Text_IO may be raised by the preceding procedures in the appropriate circumstances, as for the corresponding procedures of Text_IO.Float_IO. 

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