[ruby-core:17241] Re: Enumerable::Enumerator#with_memo

Hi --

On Sat, 14 Jun 2008, Jeremy Kemper wrote:

> On Fri, Jun 13, 2008 at 8:28 AM, Akinori MUSHA <[e-mail]> wrote:
>> Thank you all for your voices!
>>
>> At Wed, 4 Jun 2008 03:28:03 +0900,
>> I wrote:
>>> with_object:
>>>     - not bad, but too unspecific and a bit too long to use often
>>
>> On second thoughts, `with_object' sounds just fine and simply better
>> than with_memo.  A method that does many things deserves a long name,
>> with the word `object' giving a user an impression that passing an
>> immutable object may be useless.
>>
>> So, I'd take `with_object' as the safest choice.
>>
>>
>> Among your opinions and ideas, I personally liked `returning', but it
>> is too bad it does not say anything about adding a parameter.
>>
>> Let me note, as a few people already pointed out, that making method
>> chains `readable' as English is not a requisite here.  Making Ruby
>> sound like English makes things at some points in some use cases
>> easier, but going too far it often spoils simplicity, intuitiveness
>> and consistency.
>>
>>
>> Now, I was so inspired by your options such as `traverse_with' and
>> `subject' (as a noun), but I'm still thinking that there could be a
>> better one word verb.  Here are some I thought up.
>>
>> bring:
>>  -- brings an object through the iteration (back to where it was)
>>
>> introduce:
>>  -- introduces an object to the block and to the whole expression
>>  (implying that the object is the subject, i.e. return value)
>
> I think introduce is very good name.
>
>  * it's a verb describing the same behavior as with_object
>  * it's more succinct, in the spirit of map, select, inject
>  * it's obvious that it introduces a block param
>  * it implies that the introduced arg will be the return value

Wouldn't the return value depend on the method you're chaining it to
though, like with_index? For example, I would expect this:

   [1,2,3].map.introduce(obj) {|a,b| ... }

to return not obj but a mapping of [1,2,3]. Similarly, this:

   [1,2,3].select.introduce(obj) {|a,b| <some test of a and/or b> }

I would expect to return a selected subset of [1,2,3]. I'm probably
vastly misunderstanding the whole point of the method.

I think I'm in favor of the bland but congruent with_object. The
nearness of with_index and with_object appeals to me, especially given
how many new terms and naming idioms there are in 1.9 already.


David

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