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I feel like instance_eval deserves a friendlier name. Especially when used in tandem with a block to reach down inside an object for a moment.

A great example of this is on the RubyGarden wiki under RubyStyleGuide/InjectComplexTestsIntoObjects. The challenge is to reduce the redundancy of the below.

 f = open("myfile")
 if f.stat.readable? and f.stat.writable? and f.stat.size? and f.stat.owned?
   # work with file
 end

My favorite solution involves instance_eval, but see how long and ugly it looks? Perhaps an answer would be aliasing a name like within for simple block calls to instance_eval.

 f = open("myfile")    
 if f.stat.instance_eval{ readable? and writable? and size? and owned? }
   # work with file
 end