Gobal and Local variable identifier

[kaedusoft]

Hi. I have a very simple question but I have not been able to solve it in Pascal. Obviously I know that when a local variable (within a procedure or function) has the same name (identifier) ​​as a global variable, the local variable takes precedence and overshadows the global variable. My question is: Is there any way to overcome this and see a global variable with the same name as a local variable? In languages ​​like C this is possible, but I can not find how to do it in Pascal.

Thanks you very much for your help and your time.

[lucamar]

My question is: Is there any way to overcome this and see a global variable with the same name as a local variable?

Nope, the variable in local scope hides completely the global variable unless it's in another (used) unit and you fully qualify the reference, as in uglobals.MyVar := ...

[Martin_fr]

You can prefix the global var with the unit name of the unit in which it is defined.
Unless you have other identifiers (eg vars) that much the unit name.

Code: Pascal  [Select][+][-]

1. UnitName.Globalvar

Works within the current unit too.

[jamie]

I requested a compiler enhancement a while ago to where you could just place a DOT to the left without the unit name and it
would simply step back in scope. I guess that didn't fly.. You can do it in C/C++ 

[kaedusoft]

Thank you. Using unit.variable works well, even in the main program using projectName.variable. The most curious thing is that I knew how to use this for the units, but I never realized to use it in the main program.

Thank you very much for your time.

[JuhaManninen]

I requested a compiler enhancement a while ago to where you could just place a DOT to the left without the unit name and it
would simply step back in scope. I guess that didn't fly.. You can do it in C/C++ 

That sounds counter-intuitive and prone to errors. C++ may not be the best example for clear and readable code. I am happy your request did not fly. :-)
Why such tricks are needed? Why not just give unique names for variables?

[jamie]

Don't knock it until you try it..

using a single "." to back step into the global spec of the current unit would be the same as simply
specifying the current unit in scope, just a lot shorter..

 But I am glad you are happy now, we wouldn't want any disgruntle coders on site.

 Have a peachy day and may your successes be many!

 Oh, did I forget to mention that I am glad you are happy, it makes me happy, too!
 
 73's

[creaothceann]

This is also possible with absolute:

Code: [Select]

unit u;

var
        b  : byte;
        b_ : byte absolute b;

procedure p(const b : byte);
begin
b_ := b + 1;
end;

begin
p(2);
WriteLn(b);  // 3
end.

[mangakissa]

Hi. I have a very simple question but I have not been able to solve it in Pascal. Obviously I know that when a local variable (within a procedure or function) has the same name (identifier) ​​as a global variable, the local variable takes precedence and overshadows the global variable. My question is: Is there any way to overcome this and see a global variable with the same name as a local variable? In languages ​​like C this is possible, but I can not find how to do it in Pascal.

Thanks you very much for your help and your time.

What's the problem to use different names:
class :  fname
global / public: gname
local : name

[Thaddy]

In languages ​​like C this is possible, but I can not find how to do it in Pascal.

Thanks you very much for your help and your time.

In C this is also not possible.... Maybe you confuse it with case sensitivity of C. In that case the variables actually do not have the same name, C is case sensitive. So variable Test and TEST are different.
In Pascal you need to have two different names, because Pascal is NOT case sensitive, so variable Test and TEST are the same.

Note that it is possible to have and access with the same name if they are not in the same unit: you can use unit scope, unit1.Test vs Test used in any other unit as a local.

[Zoran]

Note that it is possible to have and access with the same name if they are not in the same unit: you can use unit scope, unit1.Test vs Test used in any other unit as a local.

As Martin said, works with same unit too.

Interestingly, I tested and it works not only in units, but also in main program this way:

Code: Pascal  [Select][+][-]

1. program Project1;
2.  
3. // Tested with these modes, works same:
4. {$mode fpc}
5. //{$mode objfpc}
6. //{$mode delphi}
7.  
8. uses
9.   SysUtils;
10.  
11. var
12.   X: LongInt;
13.  
14.   function Test22: AnsiString;
15.   var
16.     X: AnsiString;
17.   begin
18.     X := 'TestProject'; // local variable
19.     Project1.X := 22; // global variable
20.  
21.     Exit(X + Project1.X.ToString);
22.   end;
23.  
24. begin
25.   writeln(Test22);
26.   writeln(X); // assigned in Test22 call.
27. end.
28.  

output:

TestProject22
22