CODEWITHSUNDEEP
stringada
SquidsEnMasse
SquidsEnMasse

Reputation: 726

Ada fill constant string with Nulls

I want to make a constant string that looks like:

My_Null_String : constant String(1 .. 50) := "NULL***********************";

with all of the *s being Ascii.Nul characters. It is not possible to do this via the others keyword, as in:

My_Null_String : constant String(1 .. 50) := "NULL" & (others => Ascii.Nul);

Is there an elegant solution to this that doesn't involve a huge block of Ascii.Nul characters to fill out the rest of my string?

Thanks

Upvotes: 2

Views: 1207

Answers (2)

egilhh
egilhh

Reputation: 6430

How about: 

My_Null_String : constant String(1 .. 50) := ('N','U','L','L', others => ASCII.Nul);

Upvotes: 1

ajb
ajb

Reputation: 31699

My_Null_String : constant String(1 .. 50) := "NULL" & (5 .. 50 => ASCII.NUL);

The problem with your original attempt is that in order to evaluate

(others => ASCII.NUL)

the program has to have a way to determine the bounds. It doesn't, and it's not smart enough to make calculations such as figuring out that this is formed by concatenating two strings and therefore we can figure out that the bounds should be whatever is left over after the first string is evaluated. The language would have to make a special case just for this (array concatenation), and it doesn't.

Upvotes: 3

Related Questions