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Groovy / Closures

Memoized closures

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

10 min read • Beginner

Memoized closures is a focused Groovy lesson inside Closures. The example uses the construct named in the lesson directly rather than reusing a generic placeholder.

Trace the example from its inputs through Memoized closures 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-0028-1094f51a78.groovy
groovy Try It Live 
def multiply = { int a, int b -> a * b }
def timesTen = multiply.curry(10)
assert timesTen(4) == 40
assert [1,1,2].unique() == [1,2]
assert [a:1,b:2].find { it.value == 2 }.key == "b"
Edge case / engineering note

For Memoized closures, 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

Memoized closures Mastery Check →
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Composition with rightShift