Which of the following Ruby code snippets correctly defines a closure using Proc.new?

easy📝 Syntax Q3 of 15

Ruby - Blocks, Procs, and Lambdas

Which of the following Ruby code snippets correctly defines a closure using Proc.new?

Aproc = Proc.new { |x| x * 2 }

Bproc = Proc.new(x) { x * 2 }

Cproc = Proc.new do x; x * 2 end

Dproc = Proc.new { x -> x * 2 }

Step-by-Step Solution

Solution:

Step 1: Understand Proc.new syntax
Proc.new takes a block and creates a closure capturing variables.
Step 2: Analyze options
proc = Proc.new { |x| x * 2 } correctly uses Proc.new with a block and a parameter |x|. proc = Proc.new(x) { x * 2 } has incorrect syntax for parameters. proc = Proc.new do x; x * 2 end incorrectly uses semicolon and block syntax. proc = Proc.new { x -> x * 2 } uses invalid lambda syntax inside Proc.new.
Final Answer:
proc = Proc.new { |x| x * 2 } -> Option A
Quick Check:
Valid Proc syntax uses block with parameters in pipes [OK]

Quick Trick: Proc.new requires block with parameters in pipes [OK]

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