# Changelog

All notable changes to `chemidentifier` are documented here. Versions
follow the number given to `\ProvidesExplPackage`/`\ProvidesExplFile`.

## 2.0.1 — 2026-09-20

### Fixed

- `\chemidscheme` crashed with a raw Lua error
  (`attempt to index a nil value`) when used before any `\chemidkey`
  or `\chemidnote` had run earlier in the document. An unlabelled
  scheme (a lone structure, a graphical abstract, a figure whose
  labels are already typeset) is a legitimate use of `\chemidscheme`
  and is now simply typeset verbatim. Fixed identically in
  `chemidentifier-v2.sty` and the frozen `chemidentifier-v1.sty`.
- The text substitution performed by `\chemidscheme` was a plain,
  unanchored substring replacement applied to *every* line of the
  `.pdf_tex`, including the `\includegraphics` line. A motif that
  happens to be a substring of the companion PDF's file name — easy to
  trigger, since both are usually named after the compound — rewrote
  the image path itself and broke the figure with an obscure
  `\csname` error. The `\includegraphics` line is now left untouched,
  and a new warning names the motif and the figure when this would
  have happened, instead of failing silently downstream.

### Changed

- **`links` (version 2, `\chemidsetup`) now defaults to `false`
  instead of `true`.** Compounds are typeset as plain numbers by
  default; add `links=true` — as a package option
  (`\usepackage[links=true]{chemidentifier}`) or via `\chemidsetup` —
  to restore clickable links and anchors as before. This only affects
  version 2 (`\usepackage[version=2]` or the default); version 1 has
  no `links` key and is unaffected.

## 2.0.0 — 2026-08-19

Initial CTAN release of version 2, alongside the frozen version 1.