Assigning value failed? a basic question

[joshatt]

#property indicator_chart_window

extern string a="1111";
string b;

int init()
  {
   //--- 3 lines ---
   if(b=="")
      b=a;
   Print(b);
   //-------------------
   return(0);
  }
.....

I bring down my actual problem to the above simple experiment, and variable b always keeps empty value. It's all the same if I move these 3 lines to start().

How so?

[Alexandre Borela]

joshatt:

I bring down my actual problem to the above simple experiment, and variable b always keeps empty value. It's all the same if I move these 3 lines to start().

How so?

b is NULL.

#property indicator_chart_window

extern string a="1111";
string b;

int init()
  {
   //--- 3 lines ---
   if(b==NULL)
      b=a;
   Print(b);
   //-------------------
   return(0);
  }

[joshatt]

Alexandre Borela:
b is NULL.

Thank you, sir, you made my day!