Control Flow
While Loop in Swift
The while loop executes a block of code while a boolean expression evaluates to true. It terminates as soon as the expression evaluates to false. The boolean expression is evaluated before each iteration.
Syntax
while booleanExpression {
//block of code to be executed
}Notes
Because the boolean expression is evaluated before each iteration, the block of code executes ONLY if the booleanExpression evaluates to true. If a guarantee is needed for the block of code to run at least once, use the do-while loop.
booleanExpression results in either a true or false output. It is created using comparing operators (==, >, =, <=, !=).
There can also be multiple boolean expressions within the parentheses (booleanExpression). The boolean expressions are connected through logical operators (&&, ||, !).
Example
var x = 0;
while x < 10 {
print "\(x)" //prints x until x < 10 evaluates to false
x = x + 1
}