什么是PHP的紧凑型Ruby相当于什么？

def foo
  name = 'David'
  age = 25
  role = :director
  ...
  # How would you build this:
  # { :name => 'David',:age => 25,:role => :director }
  # or
  # { 'name' => 'David','age' => 25,'role' => :director }
end

$foo = compact('name','age','role');

我的原始答案得到了显着改善.如果从Binding本身继承,它会更清晰. to_sym就在那里,因为旧版本的ruby将local_variables作为字符串.

实例方法

class Binding
  def compact( *args )
    compacted = {}
    locals = eval( "local_variables" ).map( &:to_sym )
    args.each do |arg|
      if locals.include? arg.to_sym
        compacted[arg.to_sym] = eval( arg.to_s ) 
      end 
    end 
    return compacted
  end
end

用法

foo = "bar"
bar = "foo"
binding.compact( "foo" ) # => {:foo=>"bar"}
binding.compact( :bar ) # => {:bar=>"foo"}

原始答案

这是我能找到的行为类似PHP的compact的最接近的方法 –

方法

def compact( *args,&prok )
  compacted = {}
  args.each do |arg|
    if prok.binding.send( :eval,"local_variables" ).include? arg
      compacted[arg.to_sym] = prok.binding.send( :eval,arg ) 
    end
  end 
  return compacted
end

示例用法

foo = "bar"
compact( "foo" ){}
# or
compact( "foo",&proc{} )

但它并不完美,因为你必须通过一个过程.我愿意接受如何改进它的建议.