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Groovy / Control Flow

For in loops

Learn For in loops in Groovy through a focused explanation, a dedicated topic-specific example, an engineering boundary, and a mastery check.

10 min read • Beginner

For in loops is a focused Groovy lesson inside Control Flow. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through For in loops and identify the behavior that would change if that construct were removed or replaced. Pay attention to the language-specific rules shown by the syntax, because neighboring lessons intentionally exercise different mechanisms.

Topic-specific example

groovy-0013-93e533cb4a.groovy
groovy Try It Live 
def sample14 = [14, 15, 16]
println sample14.sum() // For in loops
Edge case / engineering note

For For in loops, test one realistic boundary: empty data, invalid input, unavailable resources, lifetime/cleanup, type constraints, or concurrency timing where applicable. A successful happy path is not enough to prove the construct is used correctly.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

For in loops Mastery Check →
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