blocks|key|716680|text|offset+=+2
some_array[offset..-1].each_with_index{%7Citem,+index%7C+some_func(item,+index%2Boffset)+}|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|716681|unstyled|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|G|8|@]|9|@]|A|$B|C]]|$1|D|3|-4|5|E|7|H|8|@]|9|@]|A|$]]]|F|$]]

<pre><code>offset = 2
some_array[offset..-1].each_with_index{|item, index| some_func(item, index+offset) }
</code></pre>

blocks|key|716750|text|实际上，Enumerator#with_index接收offset作为可选参数：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|716751|[:foo,+:bar,+:baz].to_enum.with_index(1).each+do+%7Celem,+i%7C
++puts+"#{i}:+#{elem}"
end|code-block|syntax|javascript|716752|输出：|716753|1:+foo
2:+bar
3:+baz|716754|顺便说一句，我认为它只在1.9.2中有。|716755|entityMap|0|LINK|mutability|MUTABLE|url|http://www.ruby-doc.org/core/classes/Enumerator.html#M000303^0|4|L|4|L|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]]|D|@$9|11|A|12|1|13]]|E|$]]|$1|F|3|G|5|H|7|14|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|15|8|@]|D|@]|E|$]]|$1|M|3|N|5|H|7|16|8|@]|D|@]|E|$I|J]]|$1|O|3|P|5|6|7|17|8|@]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|18|8|@]|D|@]|E|$]]]|R|$S|$5|T|U|V|E|$W|X]]]]

Actually, <a href="http://www.ruby-doc.org/core/classes/Enumerator.html#M000303"><code>Enumerator#with_index</code></a> receives offset as an optional parameter:

<pre><code>[:foo, :bar, :baz].to_enum.with_index(1).each do |elem, i|
 puts "#{i}: #{elem}"
end
</code></pre>

outputs:

<pre><code>1: foo
2: bar
3: baz
</code></pre>

BTW, I think it is there only in 1.9.2.

blocks|key|932840|text|如果some_index在某种程度上有意义，那么可以考虑使用散列，而不是数组。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|932841|entityMap^0|2|A|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|K|8|@]|D|@]|E|$]]]|G|$]]

If <code>some_index</code> is somehow meaningful, then consider using a hash, rather than an array.

blocks|key|716878|text|我撞上了它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|716879|我的解决方案不一定是最好的，但它对我很有效。|716880|在视图迭代中：|716881|只需添加:索引%2B1|716882|对于我来说，这就是全部，因为我没有使用任何对这些索引号的引用，而只是为了在列表中显示。|716883|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|N|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|O|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|P|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|K|$]]

I ran into it.

My solution not necessary is the best, but it just worked for me.

In the view iteration:

just add: index + 1

That's all for me, as I don't use any reference to those index numbers but just for show in a list.

blocks|key|932964|text|艾丽尔是对的。这是处理这个问题的最好方法，而且也不是那么糟糕|type|unstyled|depth|inlineStyleRanges|entityRanges|data|932965|ary.each_with_index+do+%7Ca,+i%7C
++puts+i+%2B+1
++#other+code
end|code-block|syntax|javascript|932966|这是完全可以接受的，而且比我见过的大多数解决方案都要好。我一直认为这就是#inject的for...oh+well。|932967|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Ariel is right. This is the best way to handle this, and it's not that bad

<pre><code>ary.each_with_index do |a, i|
 puts i + 1
 #other code
end
</code></pre>

That is perfectly acceptable, and better than most of the solutions I've seen for this. I always thought this was what #inject was for...oh well.

blocks|key|932988|text|另一种方法是使用map|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|932989|some_array+=+[:foo,+:bar,+:baz]
some_array_plus_offset_index+=+some_array.each_with_index.map+{%7Citem,+i%7C+[item,+i+%2B+1]}
some_array_plus_offset_index.each{%7Citem,+offset_index%7C+some_func(item,+offset_index)+}|code-block|syntax|javascript|932990|entityMap^0|8|3|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

Another approach is to use <code>map</code>

<pre><code>some_array = [:foo, :bar, :baz]
some_array_plus_offset_index = some_array.each_with_index.map {|item, i| [item, i + 1]}
some_array_plus_offset_index.each{|item, offset_index| some_func(item, offset_index) }
</code></pre>

blocks|key|933039|text|这在每个ruby版本中都有效：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|933040|%25W(one+two+three).zip(1..3).each+do+%7Cvalue,+index%7C
++puts+value,+index
end|code-block|syntax|javascript|933041|对于泛型数组：|933042|a.zip(1..a.length.each+do+%7Cvalue,+index%7C
++puts+value,+index
end|933043|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

This works in every ruby version:

<pre><code>%W(one two three).zip(1..3).each do |value, index|
 puts value, index
end
</code></pre>

And for a generic array:

<pre><code>a.zip(1..a.length.each do |value, index|
 puts value, index
end
</code></pre>

blocks|key|717040|text|下面使用Ruby的枚举器类，非常简洁。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|717041|[:foo,+:bar,+:baz].each.with_index(1)+do+%7Celem,+i%7C
++++puts+"#{i}:+#{elem}"
end|code-block|syntax|javascript|717042|输出|717043|1:+foo
2:+bar
3:+baz|717044|Array#each返回一个枚举器，调用Enumerator#with_index返回另一个枚举器，一个块被传递到该枚举器。|717045|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|S|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

The following is succinct, using Ruby's Enumerator class.

<pre><code>[:foo, :bar, :baz].each.with_index(1) do |elem, i|
 puts "#{i}: #{elem}"
end
</code></pre>

output

<pre><code>1: foo
2: bar
3: baz
</code></pre>

Array#each returns an enumerator, and calling Enumerator#with_index returns another enumerator, to which a block is passed.

Can I define the offset of the index in the each_with_index loop iterator?
My straight forward attempt failed:

<pre><code>some_array.each_with_index{|item, index = 1| some_func(item, index) }
</code></pre>

Edit:

Clarification: I don't want an array offset I want that the index within the each_with_index doesn't start from 0 but e.g. 1.

Ruby each_with_index offset

我可以在each_with_index循环迭代器中定义索引的偏移量吗？我的直接尝试失败了：some_array.each_with_index{|item, index = 1| some_func(item, index) }编辑：澄清:我不想要数组偏移量，我希望each_with_index中的索引不是从0开始，而...

问拼音each_with_index偏移量
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