Ruby:从数组中删除第一个元素最简单的方法是什么?

Lets say I have an array

假设有一个数组。

[0, 132, 432, 342, 234]

What is the easiest way to get rid of the first element? (0)

去掉第一个元素最简单的方法是什么?(0)

11 个解决方案

#1

"pop"ing the first element of an Array is called "shift" ("unshift" being the operation of adding one element in front of the array).

“pop”数组的第一个元素被称为“shift”(“unshift”是在数组前面添加一个元素的操作)。

#2

Use the shift method on array

在数组上使用shift方法。

>> x = [4,5,6]
=> [4, 5, 6]                                                            
>> x.shift 
=> 4
>> x                                                                    
=> [5, 6] 

If you want to remove n starting elements you can use x.shift(n)

如果你想移除n个起始元素，你可以使用x。shift(n)

#3

a = [0,1,2,3]

a.drop(1)
# => [1, 2, 3] 

a
# => [0,1,2,3]

and additionally:

另外:

[0,1,2,3].drop(2)
=> [2, 3]

[0,1,2,3].drop(3)
=> [3] 

#4

[0, 132, 432, 342, 234][1..-1]
=> [132, 432, 342, 234]

So unlike shift or slice this returns the modified array (useful for one liners).

因此，与shift或slice不同的是，它返回了修改后的数组(对于一个内层来说是有用的)。

#5

This is pretty neat:

这是非常整洁:

head, *tail = [1, 2, 3, 4, 5]
#==> head = 1, tail = [2, 3, 4, 5]

As written in the comments, there's an advantage of not mutating the original list.

正如在评论中所写的，没有改变原始列表是有好处的。

#6

or a.delete_at 0

或a.delete_at 0

#7

Use shift method

使用转换方法

array.shift(n) => Remove first n elements from array 
array.shift(1) => Remove first element

https://ruby-doc.org/core-2.2.0/Array.html#method-i-shift

https://ruby-doc.org/core-2.2.0/Array.html method-i-shift

#8

You can use:

您可以使用:

a.slice!(0)

slice! generalizes to any index or range.

片!概括到任何索引或范围。

#9

You can use Array.delete_at(0) method which will delete first element.

您可以使用Array.delete_at(0)方法来删除第一个元素。

 x = [2,3,4,11,0]
 x.delete_at(0) unless x.empty? # [3,4,11,0]

#10

You can use:
arr - [arr[0]] or else arr - [arr.shift()] or simply arr.shift(1)

您可以使用:arr - [arr[0]]或其他arr - [arr.shift()]或简单的arr.shift(1)

#11

You can use:

您可以使用:

 a.delete(a[0])   
 a.delete_at 0

Both can work

都可以工作