in reply to Re^4: Regex: Identifying comments
in thread Regex: Identifying comments

umm..
No.

You will not see my regex fault with your examples. My regex will stumble with this sql. 

update set bar = bar - 1 ; -- subtraction symbol may disappear.

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I expected to see SQL parser solution in this thread, like this 

my $p = SQLParser->new(type=>'mysql', sql=>$sql)
  or die SQLParser->error();

$p->prettyprint(1);
$p->without_comment(1);
print $p->sql;

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At first I looked SQL::Parser. It seems quite near for such tasks, but I couldn't find good solution to rip off comments. Do you know such module?

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Re^6: Regex: Identifying comments
by pvaldes (Chaplain) on Aug 31, 2012 at 15:32 UTC 
    use strict; use warnings;

while (<DATA>) {
    chomp; 
    next if /^\s*--/;
    print $_,"\n" if !/--/;
    elsif (/--/ && !/--(.*?);/){
         s/--(.*?)$//;
        print $_,"\n"}
    elsif (/--(.*?);\s*--(.*?)$/){
         s/\s*--$2//;
         print $_,"\n"}
    else { print $_,"\n"}
}

__DATA__
select 'text' from foo;       -- comment
select '--Not comment' from foo;        --But this is
select q from z; -- as is this
select '--Not this' + '--either' from foo;
select 'qaws' + make from "a"; -- comment with 'a' quote
select 'a' from 'b' with 'c' -- comment with 'a --' comment
-- test comment (add1)
select 'text\'s' from foo    --escaped  ... (add2)
select 'text\'s' from foo        --escaped'  ... (add3)
update set bar = bar - 1 ; -- subtraction symbol preserved
create table ( -- fo
field text, -- fufufu
field int)

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[reply]
[d/l]

      I think you need to revisit this... 

      syntax error at 991028.pl line 7, near "elsif"
syntax error at 991028.pl line 10, near "elsif"
syntax error at 991028.pl line 12, near ""\n"}"
Execution of 991028.pl aborted due to compilation errors.

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[reply]
[d/l]
        first elsif should probably be "if" only
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