Announcing Building Git

Re:Announcing Building Git by kccqzy on Tuesday April 09, 2019 @10:08PM (#19621139)

Far from it. Ruby blocks aren't really lambdas or anonymous functions. For example when you use return inside a block, it's not just the code in the block is being returned, but the whole enclosing function. And, you don't really "call" a block but yield to it. It's not even an object that you can inspect. It's syntax. It's really a new kind of control structure. Ruby blocks have few equivalents in other languages.

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Re:Announcing Building Git by localhostdotdev on Tuesday April 09, 2019 @10:33PM (#19621281)

   def f(&block)
     block.class
   end

   f { } # => Proc
   f(&-> { }) # => Proc
   f(&lambda { }) # => Proc
   f(&:something) # => Proc

   lambda { }.class # => Proc (I think you get the idea)

   method(:f).class # => Method

   lambda { |i| i + 1 }.call(10) # => 11

you don't typically return in a block, there is implicit return. you would do "next" or "break" depending on what you want to achieve. as far as I know that's the main difference between procs and methods.

(not that anybody would do what I do, most people just use blocks, some people use yield, few people use the &block argument, but that's exactly the same)

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Re:Announcing Building Git by ptx on Wednesday April 10, 2019 @02:28AM (#19622333)

Sound a lot like inlined lambdas in Kotlin. Lambdas can be passed with the same block-like syntax, and when they're marked as "inline" you can return from the enclosing function from within the lambda (because the lambda will have its body inlined by the compiler).

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