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Control Structure

Similar to many other languages on Arduino we have control structures, some of this structure are:

From this the new one (in comparison with python and swift ) will be the goto.

As other language we have ways to jump to return a value, go to the next item, or break the loop all together, for those task we have:

I won't add much about break, continue, and return since they work like in another languages, same as some of the control structures. Although, I will add the syntax of some of those items, to quick reference.

do...while

Work similar to while loop, with the exception the condition is evaluated at the end of the loop, so the loop aways run at least one time.

Syntax 

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do {
  // statement block
} while (condition);

Example 

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int x = 0;
do {
  delay(50);          // wait for sensors to stabilize
  x = readSensors();  // check the sensors
} while (x < 100);

while

Like any other while loop, i will loop until the condition become False

Syntax 

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while (condition) {
  // statement(s)
}
Example 
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var = 0;
while (var < 200) {
  // do something repetitive 200 times
  var++;
}

switch...case

"switch case controls the flow of programs by allowing programmers to specify different code that should be executed in various conditions"

  • var: a variable whose value to compare with various cases. Allowed data types: int, char.
  • label1, label2: constants. Allowed data types: int, char.

Syntax 

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switch (var) {
  case label1:
    // statements
    break;
  case label2:
    // statements
    break;
  default:
    // statements
    break;
}
Example 
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switch (var) {
  case 1:
    //do something when var equals 1
    break;
  case 2:
    //do something when var equals 2
    break;
  default:
    // if nothing else matches, do the default
    // default is optional
    break;
}

goto

Transfers program flow to a labeled point in the program.

Syntax 

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label:

goto label; // sends program flow to the label

Example 

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for (byte r = 0; r < 255; r++) {
  for (byte g = 255; g > 0; g--) {
    for (byte b = 0; b < 255; b++) {
      if (analogRead(0) > 250) {
        goto bailout;
      }
      // more statements ...
    }
  }
}

bailout:
// more statements ...

The use of goto is discouraged in C programming