ios - Divided operation in Swift -

why error on that?

 var rotation:float= double(arc4random_uniform(50))/ double(100-0.2) 

actually try 1 too:

 var rotation:double= double(arc4random_uniform(50))/ double(100-0.2) 

thank you

swift has strict rules whitespace around operators. divide '/' binary operator.

the important rules are:

• if operator has whitespace around both sides or around neither side, treated binary operator. example, + operator in a+b , + b treated binary operator.
• if operator has whitespace on left side only, treated prefix unary operator. example, ++ operator in ++b treated prefix unary operator.
• if operator has whitespace on right side only, treated postfix unary operator. example, ++ operator in a++ b treated postfix unary operator.

that means need add space before / or remove space after indicate binary operator:

var rotation = double(arc4random_uniform(50)) / (100.0 - 0.2) 

if want rotation float, should use instead of double:

var rotation = float(arc4random_uniform(50)) / (100.0 - 0.2) 

there no need specify type explicitly since inferred value assigning to. also, not need explicitly construct literals specific type conform type using them with.