Swift Operators - Basic Part 3 (Range operators in swift)

Range Operators:

• Closed Range operators 
• Half-Open Range Operators
• One-Sided Ranges

Closed Range Operators: 

• a...b
• It defines a range starting from a to b. 
• it includes the values of  a and b
• value a must not be greather than b

Usage:  for index in 1...5

Half-Open Range Operators: 

• a..
• It defines a range starting from a to b. 
• But it does not include b
• It is very useful, when working with the arrays. Reason it starts from 0 to count

   Usage: for index in 0..

One Sided Range operators 

Usage: 

   for name in namesArray[2...] {} it returns index 2 from till the end of array.

   for name in namesArray[...2] {} it returns index 0 from index 2. 

 

Example: 

let myRange = ...5 

range.contains(4) ==> true 

range.contains(11) ==> false 

range.contains(-4) ==> true

Logical Operators: check my previous blog post 

Swift Opertors - Basic Part 2

Comparision Operator

• Equal To (==)
• Not Equal (!=)
• Less than (<)
• Greater than (>)
• Less than or Equal to (<=)
• Greater than or Equal to (>=)

It reruns either true or false, it is used in if conditional statements.

Tubles comparision:  

                 Left to right comparision, if first element same as second then only it goes for second element comparision.

Ternary Conditional Operator:

• Question ? answer1: answer 2
• Example answer = 2 < 5 ? true: false

Nil Coalescing Operator: (??)

• a ?? b
• It unwraps an optional a if it contains a value, or returns a default value bif a is nil.
• a is an optional type here
• b must  match with the type that is stored inside a.

Swift Operators - Basic Part 1

Assignment Operators

• It initialize or updates the value of a variable with the value of b (a=b)
• It also supports tuples ((x,y) = (1,2) x -1 and y-2)
• If x= y {} this is invalid, reason it does not return anything, it just assigns. 

Arithmatic Operators

• Addition (+)
• Subtraction (-)
• Multipication (*)
• Divisions(/)

Reminder (Modulas) Operator (%) 

• 7 % 3 = 1  (3*2)+1 = 7 
• a % b means (b * multipier) + reminder = a 

Unary Minus and Unary Plus:

•   - a or + a

     Example: a = 3, then -a = -3 and +a = -3

                    +a does not change anything

Compound Assignment opertors

• It combines assignment operator with another operations.

          Example a += 2 => a = a+2

Swift Operators - Terminology

Terminology

• Unary Operators: 

• It operates on a single target.
• It appears immediately before their target or post their target

                  Example: -a , !a, a!

• Binary Operators:

• It operates on two targets
• It appears in between two targets.

               Example: 2+4, 9*5

• Ternary Operators

• It operates on three targets
• In Swift, it has only one ternary operator.

                   Example:  a ? b: c