name: stray-dollar default: false advisory: false fix: true since: 0.1.0

stray-dollar

Literal $ in prose (opt-in for projects that don't use $…$ math).

What it does

Flags $ characters in prose that are not part of a recognised math region.

Some Markdown renderers (Pandoc with --mathjax, KaTeX-aware mdBook, GitHub) treat $…$ as inline math. Authors who rely on TeX-style $ … $ instead can accidentally produce math output where they wanted a literal $5, and authors who rely on $…$ for math can produce prose where they meant math. Either way, a stray single $ in prose is almost always a typo.

This rule is opt-in because projects that consistently use $…$ for math have no use for it. The linter would flood with false positives. Turn it on in projects that standardise on $ … $ or no inline math at all.

The autofix escapes the dollar (\$); review before applying.

Example (bad)

That costs $5.

Example (good)

That costs \$5.

Configuration

This rule is off by default. Enable with [lint] extend-select = ["stray-dollar"].
Disable inline: .
Severity: non-advisory. Safe autofix available.

References

Pandoc Markdown: math extension.
mdwright treats $ … $, \[ … \], and named environments as math regions; $…$ is excluded by default because it conflicts with literal-dollar prose.

mdwright