Tag   Meaning
  ----|----------------------
   *    Always include line
   &    Include line if ALL parameters and dependencies are true.
   |    Include line if ANY parameters and dependencies are true.
   #    Never include line, i.e. this line is a comment


##</code><code>##

  Symbol | Meaning           | Example | In Query     | Bind Var
 --------|-------------------|---------|--------------|----------  
  ??       Named Placeholder  ?foo?      '?'            YES
  !!       Dependency         !foo!      Empty string   NO
  !~!      Negated Dependency !~foo!     Empty string   NO      

##</code><code>##


my $sql = <<'END';
#  TAG  CODE with PLACEHOLDERS and DEPENDENCIES
    *   SELECT
    &       count(*),  !want_count!
    &       some,      !want_data! 
    &       stuff,     !want_data!
    *   WHERE
    *           foo = ?foo?
    &       AND bar = ?bar?
    &   ORDER BY someting  !want_data!
    &   LIMIT  ?page_size? !want_data!
    &   OFFSET ?offset?    !want_data!
END

my ($query, @bind_vars) = DBIx::PreQL->build_query(
    query => $sql,
    data  => {
        foo        => $foo,
        bar        => $bar,
        want_count => !!$count_only,
        want_data  => !$count_only, 
        page_size  => $page_size,
        $offset    => $page_size * $page_number,
    },
);


##</code><code>##

SELECT
    some, 
    stuff
WHERE
        foo = ?
    AND bar = ?
ORDER BY someting
LIMIT  ?
OFFSET ?

BINDVARS:   'Foolike', 'Barlike', 3, 30