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Crystal / Methods

double splat

Learn double splat in Crystal with a construct-specific explanation, unique example, engineering boundary, and mastery check.

10 min read • Intermediate

double splat is a focused Crystal topic inside Methods. This lesson explains the construct itself, the state or value it operates on, and the observable result it produces.

Read the example as a small executable experiment. Identify the exact syntax that belongs to double splat, then change one input and predict the result before running it.

Topic-specific example

crystal-03-05-double-splat.cr
crystal Try It Live 
def build(**opts)
  opts
end
p build(name: "Ada", age: 36)
Edge case / engineering note

double splat has rules that are easy to miss when the example is copied mechanically. Check the feature-specific boundary shown by this construct: scope, mutability, evaluation order, type constraints, lifetime, error behavior, compile-time restrictions, or resource cleanup where applicable.

Content source & attribution
Original Syntaxis Content · Original Syntaxis Content

Lesson quizzes

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