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iOS Swift Basics (retired) Control Flow For-Condition-Increment

Arun Sivananthan
Arun Sivananthan
1,847 Points
Posted by Arun Sivananthan
Arun Sivananthan
1,847 Points

For loop?

for var i = 0; i < todo.count; i++ { println(todo[i]) }

If i is incremented before the println function won't the first thing printed be from the second position or index 1 rather than 0?

2 Answers

Jeff Lyons
Jeff Lyons
7,243 Points
Jeff Lyons
Jeff Lyons
7,243 Points

With that For loop syntax, the increment (or decrement, as the case may be) doesn't happen until AFTER the condition in the middle has been deemed true and the actions inside the braces executed. Someone else may be able to give you a more detailed explanation, but this is my understanding:

Step 1: initialize variable (i)

Step 2: test condition (Is i less than the total number of array elements?)

Step 3: If Step 2 is YES, execute instructions inside braces and proceed to Step 4. If NO, terminate loop.

Step 4: increment i and go to Step 2