Using iteration / method chaining / etc on multi-dimensional arrays

[Chris Katko]

On Thursday, 12 April 2018 at 15:47:14 UTC, Uknown wrote:
> On Thursday, 12 April 2018 at 15:38:34 UTC, Chris Katko wrote:
>> I googled but couldn't find any clear solution.
>>
>> I've got a 2-D array of strings read from a text file I 
>> parsed. So it's like
>>
>> 0 1 15 0 0
>> 2 12 1 0 0
>> ...
>> 0 1 0 10 0
>>
>> They come in with spaces, so I join into an array between 
>> them. But then the last ones have a newline \n on the end, 
>> which explodes the to! type conversion.
>>
>> If it was a single array, I could simply do:
>>
>> string [25] test;
>>
>>   test.each((ref n) => n.stripRight());
>>
>> But how do you do that when it's a 2-D array?
>>
>> I'm looking not just for this case, but the generate case of 
>> iterating / applying filters to 2-D arrays.
>>
>> Thanks.
>
> I think something like this would work:
>
> test.each((ref s) => s.each((ref n) => n.stripRight()));
>
> Essentially, get each 1D array from the 2D array, and then 
> apply the algorithms on that. There's probably a better way 
> though

But each doesn't return anything, it mutates, right? I think 
that's the problem I ran into with my attempt. With your code, I 
get an error about void:

   string []x = split(file.readln.idup, " ");
   x.each((ref s) => s.each((ref n) => n.stripRight()));

extra.d(2493): Error: template std.algorithm.iteration.each 
cannot deduce function from argument types !()(string[], void), 
candidates are:
/usr/include/dmd/phobos/std/algorithm/iteration.d(864):        
std.algorithm.iteration.each(alias pred = "a")

extra.d(2499): Error: template std.algorithm.mutation.stripRight 
cannot deduce function from argument types !()(string), 
candidates are:
/usr/include/dmd/phobos/std/algorithm/mutation.d(2363):        
std.algorithm.mutation.stripRight(Range, E)(Range range, E 
element) if (isBidirectionalRange!Range && is(typeof(range.back 
== element) : bool))
/usr/include/dmd/phobos/std/algorithm/mutation.d(2375):        
std.algorithm.mutation.stripRight(alias pred, Range)(Range range) 
if (isBidirectionalRange!Range && is(typeof(pred(range.back)) : 
bool))

extra.d(2500): Error: template std.algorithm.mutation.stripRight 
cannot deduce function from argument types !()(string), 
candidates are:
/usr/include/dmd/phobos/std/algorithm/mutation.d(2363):        
std.algorithm.mutation.stripRight(Range, E)(Range range, E 
element) if (isBidirectionalRange!Range && is(typeof(range.back 
== element) : bool))
/usr/include/dmd/phobos/std/algorithm/mutation.d(2375):        
std.algorithm.mutation.stripRight(alias pred, Range)(Range range) 
if (isBidirectionalRange!Range && is(typeof(pred(range.back)) : 
bool))