perl stream file for regex token including scanned tokens - regex

Question

I am trying to stream a file in perl and tokenize the lines and include the tokens.
I have:
while( $line =~ /([\/][\d]*[%].*?[%][\d]*[\/]|[^\s]+|[\s]+)/g ) {
my $word = $1;
#...
}
But it doesn't work when there's no spaces in the token.
For example, if my line is:
$line = '/15%one (1)(2)%15/ is a /%good (1)%/ +/%number(2)%/.'
I would like to split that line into:
$output =
[
'/15%one (1)(2)%15/',
' ',
'is',
' ',
'a',
'/%good (1)%/',
' ',
'+',
'/%number(2)%/',
'.'
]
What is the best way to do this?

Answer 1

(?:(?!STRING).)* is to STRING as [^CHAR]* is to CHAR, so
my #tokens;
push #tokens, $1
while $line =~ m{
\G
( \s+
| ([\/])([0-9]*)%
(?: (?! %\3\2 ). )*
%\3\2
| (?: (?! [\/][0-9]*% )\S )+
)
}sxg;
but that doesn't validate. If you want to validate, you could use
my #tokens;
push #tokens, $1
while $line =~ m{
\G
( \s+
| ([\/])([0-9]*)%
(?: (?! %\3\2 ). )*
%\3\2
| (?: (?! [\/][0-9]*% )\S )+
| \z (*COMMIT) (*FAIL)
| (?{ die "Syntax error" })
)
}sxg;
The following also validates, but it's a bit more readable and makes it easy to differentiate the token types.:
my #tokens;
for ($line) {
m{\G ( \s+ ) }sxgc
&& do { push #tokens, $1; redo };
m{\G ( ([\/])([0-9]*)% (?: (?! %\3\2 ). )* %\3\2 ) }sxgc
&& do { push #tokens, $1; redo };
m{\G ( (?: (?! [\/][0-9]*% )\S )+ ) }sxgc
&& do { push #tokens, $1; redo };
m{\G \z }sxgc
&& last;
die "Syntax error";
}
pos will get you information about where the error occurred.