首次发生的无损清除:

a = [2, 4, 6, 3, 8]
n = a.index 3
a.take(n)+a.drop(n+1)

你也可以猴子修补它。我一直不明白为什么Ruby对哈希有except方法，而对数组没有:

class Array
  def except value
    value = value.kind_of(Array) ? value : [value]
    self - value
  end
end

现在你可以做:

[1,3,7,"436",354,nil].except(354) #=> [1,3,7,"436",nil]

Or:

[1,3,7,"436",354,nil].except([354, 1]) #=> [3,7,"436",nil]

我喜欢在其他答案中提到的-=[4]方式来删除值为4的元素。

但有这样一种方法:

[2,4,6,3,8,6].delete_if { |i| i == 6 }
=> [2, 4, 3, 8]

在“基本数组操作”中提到的map函数之后。

以下是一些基准:

require 'fruity'


class Array          
  def rodrigo_except(*values)
    self - values
  end    

  def niels_except value
    value = value.kind_of?(Array) ? value : [value]
    self - value
  end
end

ARY = [2,4,6,3,8]

compare do
  soziev  { a = ARY.dup; a.delete(3);               a }
  steve   { a = ARY.dup; a -= [3];                  a }
  barlop  { a = ARY.dup; a.delete_if{ |i| i == 3 }; a }
  rodrigo { a = ARY.dup; a.rodrigo_except(3);         }
  niels   { a = ARY.dup; a.niels_except(3);           }
end

# >> Running each test 4096 times. Test will take about 2 seconds.
# >> soziev is similar to barlop
# >> barlop is faster than steve by 2x ± 1.0
# >> steve is faster than rodrigo by 4x ± 1.0
# >> rodrigo is similar to niels

再次使用包含大量重复项的更大数组:

class Array          
  def rodrigo_except(*values)
    self - values
  end    

  def niels_except value
    value = value.kind_of?(Array) ? value : [value]
    self - value
  end
end

ARY = [2,4,6,3,8] * 1000

compare do
  soziev  { a = ARY.dup; a.delete(3);               a }
  steve   { a = ARY.dup; a -= [3];                  a }
  barlop  { a = ARY.dup; a.delete_if{ |i| i == 3 }; a }
  rodrigo { a = ARY.dup; a.rodrigo_except(3);         }
  niels   { a = ARY.dup; a.niels_except(3);           }
end

# >> Running each test 16 times. Test will take about 1 second.
# >> steve is faster than soziev by 30.000000000000004% ± 10.0%
# >> soziev is faster than barlop by 50.0% ± 10.0%
# >> barlop is faster than rodrigo by 3x ± 0.1
# >> rodrigo is similar to niels

甚至更大，有更多的副本:

class Array          
  def rodrigo_except(*values)
    self - values
  end    

  def niels_except value
    value = value.kind_of?(Array) ? value : [value]
    self - value
  end
end

ARY = [2,4,6,3,8] * 100_000

compare do
  soziev  { a = ARY.dup; a.delete(3);               a }
  steve   { a = ARY.dup; a -= [3];                  a }
  barlop  { a = ARY.dup; a.delete_if{ |i| i == 3 }; a }
  rodrigo { a = ARY.dup; a.rodrigo_except(3);         }
  niels   { a = ARY.dup; a.niels_except(3);           }
end

# >> Running each test once. Test will take about 6 seconds.
# >> steve is similar to soziev
# >> soziev is faster than barlop by 2x ± 0.1
# >> barlop is faster than niels by 3x ± 1.0
# >> niels is similar to rodrigo

首次发生的无损清除:

a = [2, 4, 6, 3, 8]
n = a.index 3
a.take(n)+a.drop(n+1)

另一个选择:

a = [2,4,6,3,8]

a -= [3]

结果是

=> [2, 4, 6, 8]