> > spaces before and after

the spaces before are IMHO best dealt by stripping them before splitting. °

$line =~ s/^\s+//;

Even your pseudo python code can't do this in a one-liner with split (IMHO).

But more importantly your definition of "field" is fuzzy now.

Please clarify

• how do you allow empty fields?
• are all whitespace characters as separator allowed (like tab...)?
• are multiple whitespace characters as separator allowed?

update

provided there are no "empty fields" and "multiple whitespaces" are allowed as separators:

You can use a regex like /(\S+)/g ( \S is non-whitespace, the opposite of \s)

Debugger demo:

  DB<35> $line = " a0 a1 a2 a3 a4 a5 a6 a7 a8 a9 \n"

  DB<36> x ($line =~  /(\S+)/g)[0,1,3,5,7,9]
0  'a0'
1  'a1'
2  'a3'
3  'a5'
4  'a7'
5  'a9'

  DB<37>
[download]

update

°) or by using the magic of ' ' soonix showed us here.