[C++] split kernels for strings/binary

[asfimport]

Similar to Python str.split and bytes.split, we'd like to have a way to convert str into list[str] (and similarly for bytes).

When the separator is given, the algorithms for both types are the same. Python, however, overloads strip. When given no separator, the algorithm will split considering all whitespace (unicode for str, ascii for bytes) as separator.

I'd rather see not too much overloaded kernels, e.g.

binary_split (takes string/binary separator, and maxsplit arg, no special utf8 version needed)

utf8_split_whitespace (similar to Python's version given no separator)

ascii_split_whitespace (similar to Python's version given no separator, but considering ascii, although this could work on any binary data)

there can also be rsplit versions of these, or they could be an argument.

 

Reporter: Maarten Breddels / @maartenbreddels
Assignee: Maarten Breddels / @maartenbreddels

Related issues:

• [C++] String algorithm library for StringArray/BinaryArray (is a child of)
• [R] Bindings for strsplit (is depended upon by)

PRs and other links:

• GitHub Pull Request #8271

_{Note: This issue was originally created as ARROW-9991. Please see the migration documentation for further details.}

[asfimport]

Joris Van den Bossche / @jorisvandenbossche:
And I suppose "whitespace" here is more than a split on " " ? (also multiple spaces, different kinds of newlines, tabs, etc?) In that case, a separate specialized kernel seems indeed best.

[asfimport]

Maarten Breddels / @maartenbreddels:
Indeed, and whatever Unicode specifies as 'whitespace' for the utf8 version.

[asfimport]

Antoine Pitrou / @pitrou:
Issue resolved by pull request 8271
#8271