Hour 20. Working with Blocks
What You’ll Learn in This Hour
• Comparing blocks to callbacks
• Using typedef and function pointers
• Declaring blocks
• Using blocks
Revisiting Blocks
Blocks are not new; they were a part of Smalltalk and other languages thirty or more years ago (in some cases they were referred to as closures for reasons that you see in this section). They show up in Ruby, Python, and Lisp as well. For a variety of reasons, they were not implemented on Mac OS X until Snow Leopard (10.6); they have been in iOS since version 4. Because of their long history, for many people using blocks on Mac OS X or iOS is a matter of revisiting concepts they might know from other languages or even from long-ago basic programming courses.
Blocks ...
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