how it interacts with other modules that hook ops.
- Adjust toke_scan_str logic to always show a positive effective length of
string source.
+ - Return undef from toke_scan_str if string was unterminated.
- Detect and croak if unwanted reallocation occurs during toke_scan_str.
- Avoid memory leak in toke_scan_str.
- Add MYMETA.{json,yml} to MANIFEST.SKIP and .gitignore.