I'm new in Dart. In the code bellow exception ccures :
void main(){
dynamic alpha = "String";
dynamic beta = 12;
print("Your code is so "+beta+" "+alpha);
}
Error : type 'int' is not a subtype of type 'String'
Why when we use dynamic keyword to insist on telling the compiler for doing this job it's still got error? "combining string and other types"
When you declare your variable dynamic it does not mean the variable won't have a runtime type. It means the type can change:
dynamic alpha = 'String';
print(alpha.runtimeType); // prints String
alpha = 1;
print(alpha.runtimeType); // prints int
You can't do that with var. With var the compiler will infer the type, and it's fixed after that:
var beta = 'String';
print(beta.runtimeType);
beta = 1; // error: A value of type 'int' can't be assigned to a variable of type 'String'.
print(beta.runtimeType);
When you try to do "Your code is so " + beta you use the + operator of your String with an int paramter: beta.
You can see in the documentation that the + operator of String only accepts a String:
String operator +(String other);
If you wanted to use that operator you would have to convert the int variable to String:
print('Your code is so ' + beta.toString() + ' ' + alpha);
That's not remarkably beautiful. Instead of concatenation try string interpolation:
print('Your code is so $beta $alpha');
