Is Ada truly verbose?

 

People who prefer programming language syntax derived from the C language have often argued that the Ada language is verbose because it uses entire words rather than punctuation.

Meaning	C Syntax	Ada Syntax
Begin a block	{	begin, loop
End a block	}	end, end if, end loop, end subprogram name, end task name, end protected object name, end record
Declare a function taking a single integer parameter and returning an integer value	int foo (int x);	function foo (x : integer) return integer;
Declare a 10 element integer array indexed with the values 0 through 9	int a [10];	a : array (0..9) of integer;
Write a “for” loop to sum all the elements in array a declared above.	for (int I = 0; I < 10; i++) {    sum += a [i]; }	for I in a’range loop    sum := sum + a (i); end loop;

 

Of course, not everything in Ada takes more lines of code or more typing than the equivalent program in C or C++. For instance, the following C++ program is taken from the CodesCracker website. Its purpose is to convert a user input of a hexadecimal value into the corresponding decimal value.

/* C++ Program - Hexadecimal to Decimal Conversion */             #include<iostream.h> #include<stdlib.h> #include<conio.h> #include<math.h> unsigned long convtodecnum(char hex[]); void main() {     clrscr();     unsigned long decnum;     char hex[9];     // 8 characters for 32-bit Hexadecimal Number and one for ' '        cout<<" Enter 32-bit Hexadecimal Number : ";     cin>>hex;     decnum = convtodecnum(hex);     cout<<"Value in Decimal Number is "<<decnum<<"\n";     getch(); } unsigned long convtodecnum(char hex[]) {     char *hexstr;     int length = 0;     const int base = 16;     // Base of Hexadecimal Number     unsigned long decnum = 0;     int i;     // Now Find the length of Hexadecimal Number     for (hexstr = hex; *hexstr != '\0'; hexstr++)     {        length++;     }     // Now Find Hexadecimal Number     hexstr = hex;     for (i = 0; *hexstr != '\0' && i < length; i++, hexstr++)     {        // Compare *hexstr with ASCII values        if (*hexstr >= 48 && *hexstr <= 57)   // is *hexstr Between 0-9        {            decnum += (((int)(*hexstr)) - 48) * pow(base, length - i - 1);        }        else if ((*hexstr >= 65 && *hexstr <= 70))   // is *hexstr Between A-F        {            decnum += (((int)(*hexstr)) - 55) * pow(base, length - i - 1);        }        else if (*hexstr >= 97 && *hexstr <= 102)   // is *hexstr Between a-f        {            decnum += (((int)(*hexstr)) - 87) * pow(base, length - i - 1);        }        else        {            cout<<"Invalid Hexadecimal Number \n";        }     }     return decnum; }

 

An Ada program handling the same input and results in the same output is:

-- Convert Hexadecimal string to decimal value with Ada.Text_IO; use Ada.Text_IO; procedure Main is    type Unsigned_Long is mod 2**32;    Decimal : Unsigned_Long; begin    Put ("Enter a 32 bit hexadecimal number: ");    Decimal := Unsigned_Long'Value ("16#" & Get_Line & "#");    Put_Line (Decimal'Image); exception    when Constraint_Error =>       Put_Line ("Input value is not a valid 32 bit hexadecimal number."); end Main;

 

Ada has the built-in capability to handle literal numbers represented by base 2 through base 16. The base 16 value FF is represented as 16#FF#. Ada accepts either upper or lower case representation of the hexadecimal values A through F. The program simply appends the 16# to the entered hexadecimal digits and then appends # to the end of the string. The integer’value built in attribute converts a string representation of an integer to its corresponding integer value.

The message created in response to the exception Constraint_Error is raised if the user enters a value more than 2^32 or if one of the digits is not in the range of 0 through 9 or A through F.

In this case the Ada program appears to be far less verbose than the C++ program.