Rails is not written in Ruby

Re:Rails is not written in Ruby by tyingq on Friday February 04, 2022 @06:10PM (#30214804)

I understand why Python does it this way, but this is usually where someone points out Ruby doing:

  somestring=somearray.join(' ')

Versus Python's:

  somestring=' '.join(somearray)

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Re:Rails is not written in Ruby by dragonwriter on Friday February 04, 2022 @06:17PM (#30214872)

I generally like Ruby better than Python, but Python's choice on _join_ being a string method on the thing stuck between elements rather than an collection method on the things whose elements are getting something stuck between is better.

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Re:Rails is not written in Ruby by renox on Friday February 04, 2022 @06:33PM (#30215047)

Why do you think it's better?

I don't use either Ruby or Python but I think that the first way is more natural.

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Re:Rails is not written in Ruby by renewiltord on Friday February 04, 2022 @06:37PM (#30215102)

Interesting. I model `array.join(',')` or the equivalent Py `','.join(l)` in my head as ultimately (pseudo-code):

    foldLeft(tail(array), str(head(elem)), (acc: String, elem: T) -> acc + ',' + str(elem))

Which makes the array method easier to understand than the string method. Funny how I thought it was _obvious_, but you find the opposite obvious.

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Re:Rails is not written in Ruby by mcphage on Saturday February 05, 2022 @12:05AM (#30217731)

Why? somearray is the important piece, the string is just a bit of spacing. Put the important thing first, don’t bury the lede.

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Re:Rails is not written in Ruby by pmontra on Saturday February 05, 2022 @02:29AM (#30218709)

After years of Python I can't remember which one of these are correct

  1 ",".join(["a", "b"])
  2 ["a", "b"].join(",")
  3 ",".split("a,b")
  4 "a,b".split(",")

These method names feel like active form so 1 and 3 should be correct but it's 1 and 4 despite "a,b" obviously is not splitting "," but it's splitted by it

In Ruby it's 2 and 4.

I'm out of luck twice but at least Ruby has a and b always to the left and the comma always to the right so I always remember it.

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Re:Rails is not written in Ruby by tedunangst on Friday February 04, 2022 @07:13PM (#30215451)

    print('Hello '.join('world!'))

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