/ 
Stats-LikeR-0.23

Changes for version 0.23 - 2026-07-08

  • `rename_cols` takes HoH as input
  • `write_table` prints row names as first column; writes longtable with comments
  • `assign` gains `map_cell { ... }` for in-place per-cell column edits
  • assign
    • `assign` now accepts a third kind of column value, `map_cell { ... }`, for editing an existing column in place — no "copy, substitute, return" boilerplate and no dependence on `s///r` (unavailable on the older perls this module supports).
    • Inside a `map_cell` block, `$_` is the **named column's current cell** (not the whole row), the block's return value is **ignored**, and the modified `$_` is stored back: `assign($df, 'Res.' => map_cell { s/^[A-Z]:// })`.
    • The row is still available as `$_[0]` (sibling columns), the index as `$_[1]`, and the row key as `$_[2]` (HoH only).
    • **Undef/missing cells pass through untouched** (undef in → undef out): the block is skipped for them, so `s///` never warns on an uninitialized value.
    • Supported on all three shapes; for HoA the target column must already exist. A plain `sub { ... }` is unchanged, so `map_cell` is purely additive.
    • `map_cell` is exported alongside `assign`.
    • Tests: `assign.t` (AoH + HoA) and `assign.HoH.t` gained `map_cell` coverage — in-place `s///`, `$_[0]`/`$_[1]`/`$_[2]` context, new-column-from-undef, the missing-HoA-column death path, and `no_leaks_ok` guards. Verified building and passing the full suite on perl 5.10.1, 5.12.5 (long-double), and 5.42.2.
  • `group_by`
    • Fixed group_by to honor all filter hashrefs (option 1)
    • Root cause: the XS captured only ST(3), so every filter hashref after the first was silently dropped — including the README's documented multi-hashref form.
    • Change (LikeR.xs):
    • Removed the single-ST(3) capture and the filter_hv PREINIT var.
    • Added a FOR_EACH_FILTER(body) macro that walks the arg stack from ST(3) to ST(items-1), iterating every { column => sub } pair and ANDing them together. It iterates the stack directly rather than heap-collecting the hashrefs, so a croaking filter sub still can't leak anything (verified). Non-hashref args are skipped.
    • Rewrote the filter loop in all three branches (AoH / HoA / HoH) to use the macro, keeping each branch's own value-fetch logic.
    • One build wrinkle worth noting: xsubpp parses every non-# line in the inter-XSUB region as a candidate function signature, so a /* ... */ comment there breaks the build (it tried to parse column => sub / (ST(3)..) as a signature). I moved the macro's documentation into the XSUB body (real C) and left the macro comment-free, matching the existing EVAL_FILTER style.
    • Tests (t/group_by.HoH.filter.t, 17 assertions):
    • HoH single-column filter, AND filter (both the one-hashref and separate-hashref forms now give identical results), no-match → empty hash, missing/undef target excluded despite passing the filter, and no_leaks_ok
    • Mentioning a non-existent column is now fatal.

Documentation

README.md

Modules

Stats::LikeR
Get basic statistical functions, like in R, but with Perl using XS for performance

Provides

Stats::LikeR::col
in lib/Stats/LikeR.pm

Other files