Fix Dollar Signs Command

Escapes a bare $ immediately before a digit in prose (e.g. $60 → \$60), which some downstream renderers otherwise treat as the start of KaTeX/LaTeX math.

Usage

writechoice fix dollar-signs [options]

Options

Option	Alias	Description	Default
--file <path>	-f	Fix a single MDX file	-
--dir <path>	-d	Fix MDX files in a specific directory	-
--dry-run	-	Preview changes without writing files	false
--quiet	-	Suppress terminal output	false

Why This Is Needed

A raw $ before a number in MDX prose (e.g. "costs $60") can be misread as the opening delimiter of inline math by KaTeX-aware renderers. Escaping it (\$60) keeps it as a literal dollar sign.

What Gets Converted

Any bare $ immediately followed by a digit, outside of code and outside anything that looks like real LaTeX math:

{/* Before */}
It costs $60 or $70 depending on plan.

{/* After */}
It costs \$60 or \$70 depending on plan.

What Is Left Unchanged

• $ not immediately followed by a digit (e.g. $x, $variable)
• Already-escaped \$
• Anything inside a fenced code block (``` or ~~~)
• Anything inside an inline code span
• A $...$ or $$...$$ span that looks like real LaTeX math — see below

LaTeX awareness

A $...$ span is treated as math (and left completely untouched, even if it starts with a digit) when its content contains a LaTeX marker: a backslash (\), caret (^), underscore (_), or curly brace ({/}). For example $5 \times 10^{3}$ is left alone.

This is a heuristic, not a full LaTeX parser — matching this repo's convention of pure string transforms without AST parsing. It deliberately does not treat every $...$ pair as protected, since ordinary prose with two dollar amounts on one line (e.g. "It costs $60 or $70") would otherwise be silently skipped. Only pairs containing an actual math-looking marker are protected; both amounts in a plain two-price sentence still get escaped.

Examples

# Preview what would change
writechoice fix dollar-signs --dry-run

# Fix all MDX files in the current directory
writechoice fix dollar-signs

# Fix a specific directory
writechoice fix dollar-signs -d pages/pricing

# Fix a single file
writechoice fix dollar-signs -f pages/pricing/plans.mdx

Config File

{
  "dollar-signs": {
    "dir": "pages",
    "dry-run": false,
    "quiet": false
  }
}

Safety

• Skips code fences, inline code, and LaTeX-looking $...$/$$...$$ spans
• Idempotent: an already-escaped \$ is never re-escaped
• Use --dry-run to preview before writing
• Revert with git checkout . if needed