Re: preset counter variable in a for loop --> 'has no effect' Error

[drug via Digitalmars-d-learn]

On 2/28/20 11:48 AM, Namal wrote:
Hello,
I don't understand why this simple code causes a compiler error..

import std.stdio;

void main(){

  int b = 0;

  for (b; b<3; b++){
    writeln(b);
  }
}

$Error: b has no effect

Same works perfectly fine in C++

#include <iostream>

int main(){
  int i = 0;

  for(i; i<3; i++)
    std::cout<<i<<'\n';
}

Please help me find what I am doing wrong. Thx

D compiler is smart enough to say that the first use of `b` in for loop 
is useless. Use either this variant:
```
import std.stdio;

void main(){

 int b = 0;

 for (; b<3; b++){
   writeln(b);
 }
}
```
or this:
```
import std.stdio;

void main(){

 for (int b; b<3; b++){
   writeln(b);
 }
}
```