The Digital Press

This article explains the differences between blocks, procs, and lambdas in Ruby, focusing on how they handle arguments, object status, and the return keyword.

Why it matters: Understanding these distinctions helps Ruby developers write clearer, more predictable code when working with closures and callbacks.

The big picture: Blocks are syntax, procs are objects, and lambdas are a strict subtype of procs with argument checking and different return behavior.

Summary differences: Procs are objects; blocks are not; only one block per argument list; lambdas check arguments and handle return differently.

Commenters say: Many agree blocks are syntactic sugar for procs; some note Ruby implementations can blur these distinctions internally.