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It's kind of sad that "for" is the keyword programming languages settled on for the loop construct. Ever since its counterpart "do" was dropped from the for-st

It's kind of sad that "for" is the keyword programming languages settled on for the loop construct. Ever since its counterpart "do" was dropped from the for-statement, it's just been utterly nonsensical. I mean how on earth does the word "for" convey a loop? With the recently designed languages like Go and Swift taking so many cues from the Pascal side of the ALGOL language family, how nobody thought to pick up "repeat" or "loop" is simply beyond me.

derp_dee_derp 6y ago
<do this action> for <every iteration of the loop>
laurencerowe 6y ago
> It's kind of sad that "for" is the keyword programming languages settled on for the loop construct. Many languages only use `for` to mean a for-each style loop where it reads quite naturally: Python - `for n in range(1,10)` Ruby - `for i in 0..10` Rust - `for n in 1..10` (also picked up the bare `loop`) Others support for-each style loops along with the less than ideal C-style for loop: JavaScript - `for (n of [1,2,3])` (second attempt, for-in has too many gotchas.) Java - `for (int n : {1,2,3})` Otherwise I agree that `while` reads far more naturally. I guess they must have wanted to minimize the number keywords in Go.
- UIZealot 6y ago
  It's only natural if you already know that a for-statement is a loop. "while" is no better without the "do".
  - stevewodil 6y ago
    And if statements need a corresponding "then" to make sense as well right? Your whole argument is nonsensical. Coding isn't English Write a new language and you can name everything exactly how you please, if enough people care then they will adopt the language.
- saghm 6y ago
  Interestingly, the more common way to write that in Ruby would be `(1..10).each { |i| ... }`, or (in the case of needing a multi-line block): ``` (1..10).each do |i| ... end ``` "do" does end up getting used, but only as syntax for a "block" (similar to what other languages would call a lambda). Ruby also has a shorthand for when you want to do something `n` times without caring about the iteration number: ``` 10.times do ... end ``` One final note is that loop you wrote above is actually different in Ruby than it is for Python and Rust; `x..y` is an inclusive range in Ruby, whereas `range(x, y)` in Python and `x..y` in Rust are exclusive on the right side. I think you might have realized that since you used different starting values for the other two, but you got it backwards; the Python and Rust loops will loop only nine times, whereas the Ruby one will loop 11 times. Ruby does have a syntax for exclusive ranges though; `x...y` is an inclusive range from `x` to `y - 1`. Similarly, in Rust, `x..=y` gives an inclusive range from `x` to `y`. I don't know of any way to do an inclusive range in Python other than manually, but someone with more Python knowledge might be able to provide something for that.
  - laurencerowe 6y ago
    It's been years since I last wrote Ruby so had completely forgotten that it's ranges were inclusive by default.
  - Lammy 6y ago
    You can kinda use `do` for looping with a Block and Kernel#loop :v https://ruby-doc.org/core-2.7.1/Kernel.html#method-i-loop https://ruby-doc.org/core-2.7.1/Kernel.html#method-i-loop
SilasX 6y ago
>I mean how on earth does the word "for" convey a loop? I don't know about a loop per se, but it's used in plain language when you want the same thing to be done to every element in a set. "Clean this item and put it away. Then do that for every other piece of cooking equipment." It was actually originally borrowed from its cognate für in German: >>The name for-loop comes from the English word for, which is used as the keyword in many programming languages to introduce a for-loop. The term in English dates to ALGOL 58 and was popularized in the influential later ALGOL 60; it is the direct translation of the earlier German für, used in Superplan (1949–1951) by Heinz Rutishauser, who also was involved in defining ALGOL 58 and ALGOL 60. https://en.wikipedia.org/wiki/For_loop https://en.wikipedia.org/wiki/For_loop
- UIZealot 6y ago
  > "Clean this item and put it away. Then do that for every other piece of cooking equipment." Without the "do" it's nonsensical. And that was exactly my point.
  - SilasX 6y ago
    That was just one way of phrasing it. You could just as easily put it as, "For every piece of cooking equipment, clean it and put it away."
    - UIZealot 6y ago
      There you need the word "every" to convey that it's a loop. I'd certainly agree that "for each" is much better than "for" alone.
      - ggggtez 6y ago
        "Do your homework" doesn't imply a loop either. Nor does "This could take a while" It should not be a shock that the english language doesn't naturally have a single word that can express both a condition/duration as well as a command without any other helper words. Do is superfluous. Everything in an imperative program is a request to do something.
willcipriano 6y ago
Python's "for customer in customers" can't be clearer in my opinion.
- harry8 6y ago
  "for each customer in customers" is how you'd say that in plain english. Some languages do use foreach as a keyword echoing that.
  - WorldMaker 6y ago
    In math you have the "for all customers there exists a customer that". Maybe I should write up a formal INTERCAL proposal that this should be the proper loop construct in 2020, spelled out in plain Math English like that.
naikrovek 6y ago
All languages, both human and programming, have vestigial nonsense like this. All of them. It isn't possible for languages which are used to not have them, I would say.
ggggtez 6y ago
While we're being pedantic, "do" is a terrible keyword. I mean, everything in an imperitive program is a request to "do" something. And "do ... while(x)" is a terrible construct because it hides the loop complexity far from the place where a programmer needs to see it.
- boomlinde 6y ago
  The condition of a C-like do/while loop is exactly where the programmer needs to see it: where it's evaluated. Same with the plain while loop.
- UIZealot 6y ago
  > "do" is a terrible keyword. Not at all. "do" helps a lot to make the code read like English and thus more understandable.
renewiltord 6y ago
Wish they'd called it `grob` and called `return` `bolver` so that we can accept they're just syntactic constructs instead of pointlessly assuming meaning from what are just syntactic constructs. sum = 0 grob (i=0; i<10; i++) { sum += i } bolver sum Brilliant.
- ChrisRR 6y ago
  I feel like this is what learning to program is like when english isn't your first language
  - kryth 6y ago
    Oh man, trust me, by the time you start programming, you'll have already studied English. There's no way around it since non-English documentation is miserable at best.
  - sacado2 6y ago
    I learned programming before I learned English. I was always confused by PRINT vs INPUT: which one reads and which one writes? So yeah, it could have been grob and bolver or anything.
    - renewiltord 6y ago
      Ironically, I was undone here by bad pedagogy. The text I was reading said something about "`getch` being the opposite of what you expected since you'd think it gets the character from the computer and prints it to the screen, while `putchar` does the opposite of what you expected and doesn't give you the chance to put anything into the computer". Now, clearly whoever wrote that text had their own conception of the thing, but my mental model was that the computer is executing the program so it is getting the character from me with `getch` and it is putting the character on the screen with `putchar`. So the actual functionality seemed right. But when you combined that with the text saying that it was counter-intuitive I was like "Oh okay, got to remember it was counter-intuitive. It's the opposite of what I'd think" and so the text induced me to misunderstand. Fortunately I was a child so I learned pretty rapidly that lots of people write total crap (irrespective of the conception, the author should not have pushed it so hard) and it didn't damage my mental model at all.

derp_dee_derp 6y ago

laurencerowe 6y ago

> It's kind of sad that "for" is the keyword programming languages settled on for the loop construct. Many languages only use `for` to mean a for-each style loop where it reads quite naturally: Python - `for n in range(1,10)` Ruby - `for i in 0..10` Rust - `for n in 1..10` (also picked up the bare `loop`) Others support for-each style loops along with the less than ideal C-style for loop: JavaScript - `for (n of [1,2,3])` (second attempt, for-in has too many gotchas.) Java - `for (int n : {1,2,3})` Otherwise I agree that `while` reads far more naturally. I guess they must have wanted to minimize the number keywords in Go.

UIZealot 6y ago
It's only natural if you already know that a for-statement is a loop. "while" is no better without the "do".
- stevewodil 6y ago
  And if statements need a corresponding "then" to make sense as well right? Your whole argument is nonsensical. Coding isn't English Write a new language and you can name everything exactly how you please, if enough people care then they will adopt the language.
saghm 6y ago
Interestingly, the more common way to write that in Ruby would be `(1..10).each { |i| ... }`, or (in the case of needing a multi-line block): ``` (1..10).each do |i| ... end ``` "do" does end up getting used, but only as syntax for a "block" (similar to what other languages would call a lambda). Ruby also has a shorthand for when you want to do something `n` times without caring about the iteration number: ``` 10.times do ... end ``` One final note is that loop you wrote above is actually different in Ruby than it is for Python and Rust; `x..y` is an inclusive range in Ruby, whereas `range(x, y)` in Python and `x..y` in Rust are exclusive on the right side. I think you might have realized that since you used different starting values for the other two, but you got it backwards; the Python and Rust loops will loop only nine times, whereas the Ruby one will loop 11 times. Ruby does have a syntax for exclusive ranges though; `x...y` is an inclusive range from `x` to `y - 1`. Similarly, in Rust, `x..=y` gives an inclusive range from `x` to `y`. I don't know of any way to do an inclusive range in Python other than manually, but someone with more Python knowledge might be able to provide something for that.
- laurencerowe 6y ago
  It's been years since I last wrote Ruby so had completely forgotten that it's ranges were inclusive by default.
- Lammy 6y ago
  You can kinda use `do` for looping with a Block and Kernel#loop :v https://ruby-doc.org/core-2.7.1/Kernel.html#method-i-loop https://ruby-doc.org/core-2.7.1/Kernel.html#method-i-loop

SilasX 6y ago

>I mean how on earth does the word "for" convey a loop? I don't know about a loop per se, but it's used in plain language when you want the same thing to be done to every element in a set. "Clean this item and put it away. Then do that for every other piece of cooking equipment." It was actually originally borrowed from its cognate für in German: >>The name for-loop comes from the English word for, which is used as the keyword in many programming languages to introduce a for-loop. The term in English dates to ALGOL 58 and was popularized in the influential later ALGOL 60; it is the direct translation of the earlier German für, used in Superplan (1949–1951) by Heinz Rutishauser, who also was involved in defining ALGOL 58 and ALGOL 60. https://en.wikipedia.org/wiki/For_loop https://en.wikipedia.org/wiki/For_loop

UIZealot 6y ago
> "Clean this item and put it away. Then do that for every other piece of cooking equipment." Without the "do" it's nonsensical. And that was exactly my point.
- SilasX 6y ago
  That was just one way of phrasing it. You could just as easily put it as, "For every piece of cooking equipment, clean it and put it away."
  - UIZealot 6y ago
    There you need the word "every" to convey that it's a loop. I'd certainly agree that "for each" is much better than "for" alone.
    - ggggtez 6y ago
      "Do your homework" doesn't imply a loop either. Nor does "This could take a while" It should not be a shock that the english language doesn't naturally have a single word that can express both a condition/duration as well as a command without any other helper words. Do is superfluous. Everything in an imperative program is a request to do something.

willcipriano 6y ago

Python's "for customer in customers" can't be clearer in my opinion.

harry8 6y ago
"for each customer in customers" is how you'd say that in plain english. Some languages do use foreach as a keyword echoing that.
- WorldMaker 6y ago
  In math you have the "for all customers there exists a customer that". Maybe I should write up a formal INTERCAL proposal that this should be the proper loop construct in 2020, spelled out in plain Math English like that.

naikrovek 6y ago

All languages, both human and programming, have vestigial nonsense like this. All of them. It isn't possible for languages which are used to not have them, I would say.

ggggtez 6y ago

While we're being pedantic, "do" is a terrible keyword. I mean, everything in an imperitive program is a request to "do" something. And "do ... while(x)" is a terrible construct because it hides the loop complexity far from the place where a programmer needs to see it.

boomlinde 6y ago
The condition of a C-like do/while loop is exactly where the programmer needs to see it: where it's evaluated. Same with the plain while loop.
UIZealot 6y ago
> "do" is a terrible keyword. Not at all. "do" helps a lot to make the code read like English and thus more understandable.

renewiltord 6y ago

Wish they'd called it `grob` and called `return` `bolver` so that we can accept they're just syntactic constructs instead of pointlessly assuming meaning from what are just syntactic constructs. sum = 0 grob (i=0; i<10; i++) { sum += i } bolver sum Brilliant.

ChrisRR 6y ago
I feel like this is what learning to program is like when english isn't your first language
- kryth 6y ago
  Oh man, trust me, by the time you start programming, you'll have already studied English. There's no way around it since non-English documentation is miserable at best.
- sacado2 6y ago
  I learned programming before I learned English. I was always confused by PRINT vs INPUT: which one reads and which one writes? So yeah, it could have been grob and bolver or anything.
  - renewiltord 6y ago
    Ironically, I was undone here by bad pedagogy. The text I was reading said something about "`getch` being the opposite of what you expected since you'd think it gets the character from the computer and prints it to the screen, while `putchar` does the opposite of what you expected and doesn't give you the chance to put anything into the computer". Now, clearly whoever wrote that text had their own conception of the thing, but my mental model was that the computer is executing the program so it is getting the character from me with `getch` and it is putting the character on the screen with `putchar`. So the actual functionality seemed right. But when you combined that with the text saying that it was counter-intuitive I was like "Oh okay, got to remember it was counter-intuitive. It's the opposite of what I'd think" and so the text induced me to misunderstand. Fortunately I was a child so I learned pretty rapidly that lots of people write total crap (irrespective of the conception, the author should not have pushed it so hard) and it didn't damage my mental model at all.