change the max square for grains

[glennj]

http://forum.exercism.org/t/odd-arithmetic-in-grains/8662

Since the exercise was in WIP status, no worries about invalidating existing solutions.

[BNAndras]

I think we'd need to mark the affected tests as not included in tests.toml. We're changing the descriptions, inputs, and expected values.

[kotp]

I am approving, but not saying that we must bring this in.

Still considering the value of "work with the limitations of the language to do what seems like it can not be done" as something that we often do.

[glennj]

moving the PR to draft while I ponder the reimplementation.

[glennj]

vint is failing

exercises/practice/grains/.meta/example.vim:4:17: unexpected token: -> (see vim-jp/vim-vimlparser)

Line 4 col 17 of the new example is

  let len = [a:a->strlen(), a:b->strlen()]->max()
" ..............^

Is vint going to make me do

  let len = max([strlen(a:a), strlen(a:b)])

I'm having trouble installing it locally:

$ python3 -m venv ~/python3
$ source ~/python3/bin/activate.fish
$ python3 -m pip install vim-vint
Collecting vim-vint
  Downloading vim_vint-0.3.21-py2.py3-none-any.whl.metadata (910 bytes)
Collecting PyYAML>=3.11 (from vim-vint)
  Downloading PyYAML-6.0.2-cp313-cp313-macosx_10_13_x86_64.whl.metadata (2.1 kB)
Collecting ansicolor>=0.2.4 (from vim-vint)
  Downloading ansicolor-0.3.2-py2.py3-none-any.whl.metadata (625 bytes)
Collecting chardet>=2.3.0 (from vim-vint)
  Downloading chardet-5.2.0-py3-none-any.whl.metadata (3.4 kB)
Downloading vim_vint-0.3.21-py2.py3-none-any.whl (89 kB)
Downloading ansicolor-0.3.2-py2.py3-none-any.whl (9.8 kB)
Downloading chardet-5.2.0-py3-none-any.whl (199 kB)
Downloading PyYAML-6.0.2-cp313-cp313-macosx_10_13_x86_64.whl (181 kB)
Installing collected packages: ansicolor, PyYAML, chardet, vim-vint
Successfully installed PyYAML-6.0.2 ansicolor-0.3.2 chardet-5.2.0 vim-vint-0.3.21
$ type -a vint
vint is /Users/glennj/python3/bin/vint
$ vint exercises/practice/grains/
Traceback (most recent call last):
  File "/Users/glennj/python3/bin/vint", line 5, in <module>
    from vint import main
  File "/Users/glennj/python3/lib/python3.13/site-packages/vint/__init__.py", line 1, in <module>
    from vint.bootstrap import (
    ...<3 lines>...
    )
  File "/Users/glennj/python3/lib/python3.13/site-packages/vint/bootstrap.py", line 5, in <module>
    from vint.linting.cli import CLI
  File "/Users/glennj/python3/lib/python3.13/site-packages/vint/linting/cli.py", line 4, in <module>
    import pkg_resources
ModuleNotFoundError: No module named 'pkg_resources'
$ python3 -m pip install pkg_resources
ERROR: Could not find a version that satisfies the requirement pkg_resources (from versions: none)
ERROR: No matching distribution found for pkg_resources

[glennj]

OK, going to stop here. I'm shocked that "vimlparser" can't recognize method notation.

[BNAndras]

I’ll leave it up to Victor, but I’m not sure vint is useful here. Tests are automatically generated. The example solution just needs to pass the CI so I don’t bother using a linter on the other tracks I maintain.

[kotp]

OK, going to stop here. I'm shocked that "vimlparser" can't recognize method notation.

" Helper function to add two large numbers represented as strings
function! StringAdd(num1, num2)
    let carry = 0
    let result = ''

    " Pad the shorter number with leading zeros
    let len1 = strlen(a:num1)
    let len2 = strlen(a:num2)
    if len1 < len2
        let a:num1 = repeat('0', len2 - len1) . a:num1
    elseif len2 < len1
        let a:num2 = repeat('0', len1 - len2) . a:num2
    endif

    " Add digits from right to left
    for i in range(strlen(a:num1) - 1, 0, -1)
        let sum = str2nr(a:num1[i]) + str2nr(a:num2[i]) + carry
        let carry = sum >= 10 ? 1 : 0
        let result = string(sum % 10) . result
    endfor

    " Add the last carry if it exists
    if carry > 0
        let result = '1' . result
    endif

    return result
endfunction

" Function to calculate grains on a specific square using string manipulation
function! Square(n)
    if a:n < 1 || a:n > 64
        throw 'square must be between 1 and 64'
    endif

    " Start with 1 grain on the first square
    let grains = '1'
    for i in range(2, a:n)
        " Double the grains by adding it to itself
        let grains = StringAdd(grains, grains)
    endfor

    return grains
endfunction

" Function to calculate the total grains on the chessboard using string manipulation
function! Total()
    let total = '0'

    " Accumulate grains for each square from 1 to 64
    let grains = '1'
    for i in range(1, 64)
        let total = StringAdd(total, grains)
        " Double grains for the next square
        let grains = StringAdd(grains, grains)
    endfor

    return total
endfunction

This passes vint, and I believe should also satisfy past 64 locations, though of course we want to (probably) fail past 64 from the story parameters given.

Different approach, but let me know what you think.

[glennj]

Thanks @kotp that was driving me nuts

[kotp]

Still approved, but I did not bring it in because of the wording in appends that might go too far in directing specific approach, or details of an approach we know will work.

[kotp]

I am not crazy about this line. Addition is not the only way to do this, so we will not have to necessarily do this, but it states that we will have to do so. The word "implement", with its definitions, is ambiguous, and it may the solution does not use (at least only) two operands of any kind.

Also, the exercise will have us return the values as strings, but that does not mean what the line after says it means.

Perhaps part of my angst here is the "that means" part that is stated 4 lines above as well.

How can we phrase this so that the restrictions in Vimscript is stated, but the solution is left to the exerciser to be thought and explored.

[glennj]

In other words, Vimscript cannot express any number `2^63` or greater as an integer.

Some of the tests for this exercise require 64 bit integers and thus cannot be solved using only integer arithmetic.
The tests have been written to expect the return values as strings.
How can you implement arithmetic operations that return strings?

[kotp]

How can you implement arithmetic operations that return strings?

Maybe:

"Can you solve this by avoiding numbers that are larger than the language will allow directly?"

The tests will inform that the returns must be strings, and if the tests change later, then we do not have to change that aspect. The communication is (hopefully) clear.

and thus cannot be solved using only integer arithmetic.

"which is beyond the integer size limitation of Vimscript."

The tests have been written to expect the return values as strings.

"Because of the language limitations regarding integers, the results of the calculations are tested against a string which expresses the integer value, rather than expressing the answer as Integer."

[kotp]

Also, notice that I do avoid the use of "implement" as the word has confusing definitions. "The implement implements an implementation, within another implement." This statement is clear, but unless you are a native English speaker, it is may be hard to follow.

[glennj]

Ah sh!t, I accidentally deleted the branch. I'll create a new PR