Changelog

v0.3.0 (2026-07-14)

Critical bug fix: * Column names ending in in were misinterpreted as the in operator. Fixed. * Fixed parsing of parenthesized membership lists * Fixed handling of unterminated quotes.
Made pqfilt.filter_df() match Arrow null behavior
pqfilt.filter_df(): DNF tuple validation consistent and explicit.
Added pqfilt.scan(): Arrow-native, lazily evaluated scans
Added pqfilt.write_filtered(): One-shot writer (csv or parquet) t * The CLI now uses this streaming write path.
Added public AST utilities (pqfilt.to_ast(), pqfilt.map_leaves()) and operator utilities (pqfilt.SUPPORTED_OPERATORS, pqfilt.validate_operator()).
Preserved exact integer filter literals beyond the binary64 precision limit.
Split documentation into a practical usage guide and an advanced API guide.

Critical bug in CLI: per_file option was removed in 0.2.0 but CLI still referenced it, causing a crash. Fixed.

Breaking: removed per_file parameter from read().
Added is null / is not null operators.
Added ~ prefix negation (NotExpr).
Fixed quoted literals ('a|b', 'a&b', etc.) being split on structural characters.
Fixed in/not in list items with commas inside quotes (desig in 'a,b', 'c').
Fixed boolean column filtering: True/False strings now coerce to bool before pyarrow pushdown.
Multi-file reads now use a single ds.dataset(files) call (parallel I/O).
Parquet output now uses pq.write_table to preserve Arrow type fidelity.
Added filter_df(df, filters) to apply the same filter syntax to an already-loaded DataFrame.

True/False string literals (case-insensitive) are now converted to Python bool before pyarrow, preventing type-mismatch errors on boolean columns.

list/tuple: in/not in value lists now accept bracket/parenthesis enclosures. * "desig in [1, 2, 3]" and "desig in (1, 2, 3)" work in addition to the bare comma-separated form.
Bugfix a few edge cases.

Similar fix as 0.1.3: Fixed in/not in value parsing * "desig in '356', '3200'" are preserved as strings.

Fixed quoted scalar values * "name == '42'" now correctly preserves '42' as a string instead of coercing it to the integer 42.