Control Flow Control flow statements allow you to control the execution path of your program based on one or more conditions.
If Statements The if statement executes code conditionally based on a boolean expression.
Basic If 1
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if condition {
// code to execute if condition is true
}
Example 1
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var coverage number = 85
if coverage > 80 {
printf ( "That's some pretty good coverage\n" )
}
If-Else The else clause provides an alternative code path when the condition is false.
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if condition {
// code if true
} else {
// code if false
}
Example 1
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var coverage number = 40
if coverage >= 80 {
printf ( "Coverage is at or above 80%\n" )
} else {
printf ( "Coverage is below 80%\n" )
}
Else-If Chains Multiple conditions can be checked using else if.
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if condition1 {
// code if condition1 is true
} else if condition2 {
// code if condition2 is true
} else {
// code if all conditions are false
}
Example 1
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var score number = 75
if score >= 90 {
printf ( "Grade: A\n" )
} else if score >= 80 {
printf ( "Grade: B\n" )
} else if score >= 70 {
printf ( "Grade: C\n" )
} else {
printf ( "Grade: F\n" )
}
Optional Parentheses Parentheses around conditions are optional but can be used for clarity:
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var test bool = true
if test {
printf ( "without parentheses\n" )
}
if ( test ) {
printf ( "with parentheses\n" )
}
For Loops The for statement provides various ways to create loops.
Infinite Loop A for loop without any condition runs indefinitely (use break to exit).
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for {
printf ( "This loops forever\n" )
break // exit the loop
}
Condition Loop A for loop with a condition runs while the condition is true.
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var count number = 0
for count < 5 {
printf ( "Count: %g\n" , count )
count += 1
}
Range Loop (to) Loop from 0 up to (but not including) a value.
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for var i to 3 {
printf ( "Iteration %g\n" , i )
}
// Prints: 0, 1, 2
Range Loop (from-to) Loop from a starting value up to (but not including) an ending value.
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for var i from 5 to 8 {
printf ( "Iteration %g\n" , i )
}
// Prints: 5, 6, 7
Comparison Loop Loop while a variable meets a comparison condition.
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for var i < 3 {
printf ( "Iteration %g\n" , i )
}
// Prints: 0, 1, 2
Loop Control Break Statement The break statement exits the current loop immediately.
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for var i to 10 {
if i == 5 {
break
}
printf ( "%g\n" , i )
}
// Prints: 0, 1, 2, 3, 4
Break with Depth You can break out of multiple nested loops by specifying a depth.
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for var i to 3 {
for var j to 3 {
if i == 1 && j == 1 {
break 2 // breaks out of both loops
}
printf ( "i=%g, j=%g\n" , i , j )
}
}
Continue Statement The continue statement skips the rest of the current iteration and moves to the next one.
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for var i to 5 {
if i == 2 {
continue
}
printf ( "%g\n" , i )
}
// Prints: 0, 1, 3, 4 (skips 2)
Nested Loops Loops can be nested inside other loops.
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for var i to 2 {
for var j to 2 {
printf ( "i=%g, j=%g\n" , i , j )
}
}
// Output:
// i=0, j=0
// i=0, j=1
// i=1, j=0
// i=1, j=1
Practical Examples Conditional Logic with Multiple Conditions 1
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var test1 bool = false
var test2 bool = false
var test3 bool = true
if test1 {
printf ( "test1 is true\n" )
} else if test2 {
printf ( "test2 is true\n" )
} else if test3 {
printf ( "test3 is true\n" )
} else {
printf ( "none of the conditions are true\n" )
}
// Output: test3 is true
Loop with Conditional Break 1
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var isComplete bool = false
var counter number = 0
for ! isComplete {
printf ( "Iteration %g\n" , counter )
counter += 1
if counter >= 3 {
isComplete = true
}
}
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