I'm writing a parser for a specified format (so I'm stuck with the format). I have no doubt this will lead to many questions, but here's my first:
Given a string of comma separated elements, where an element can contain a function, and functions can have commas in their arguments, how do I best grab the elements?
After looking over Merlyn's nested C comment parser and The CSV parser from Mastering Regex, I have a working solution. I'm not convinced, however, that this is the easiest/best way to do it. Comments?
#!/usr/bin/perl
$teststr="blah,blah(blah,blah(blah,blah(blah))),blah";
#This is three elements:
# blah
# blah(blah,blah(blah,blah(blah)))
# blah
# I don't have to worry about escaped parens, the file format forbids
+it.
foreach (&parse_comma($teststr)){
print "$_\n"; #This just proves that it works
}
sub parse_comma{
my $commastr=shift;
my @tags;
my $count=0;
my $carrystr="";
foreach (split(/,/, $commastr)){
$_=$carrystr.",".$_ if $carrystr;
$count=s/\(/(/g;
$count-=s/\)/)/g;
if($count){
$carrystr=$_;
}else{
$carrystr="";
push @tags, $_;
}
}
return @tags;
}