perl -E '$s="abc def ghi";@a=unpack("(a)*",$s);$x;@b;for(@a){chomp;if(ord($_)!=32){$x.=$_}else{push@b,$x;undef$x}};push@b,$x;END{say$_ for@b}'

##</code><code>##

$b[0] = 'abc';
$b[1] = 'def';
$b[2] = 'ghi';