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README.md

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+# mddiff
+
+mddiff is a tool for comparing the frontmatter of two markdown files and generating a [JSON patch](https://jsonpatch.com/) file.
+
+## Usage
+
+```
+Usage: mddiff [OPTIONS] <file> <file2>
+
+Arguments:
+  <file>   First File
+  <file2>  Second File
+
+Options:
+  -p, --pretty              Output formatted json patch
+  -a, --add                 Only output add operations
+  -m, --modify              Only output modify operations
+  -d, --delete              Only output delete operations
+  -t, --test <key> <val>    Add test case to json patch
+  -x, --exclude <JSONPATH>  Exclude json path from diff
+  -k, --keys <JSONPATH>     Only include the specified json paths in diff
+```