REGEX Reference

Very simple generated markdown reference for REGEX Pattern Matching Shorthands and whatnot.

Basic Syntax

Pattern	Description
`.`	Matches any character except a newline
`^`	Start of a line
`$`	End of a line
`*`	Matches 0 or more of the preceding character
`+`	Matches 1 or more of the preceding character
`?`	Matches 0 or 1 of the preceding character
`{n}`	Matches exactly `n` occurrences
`{n,}`	Matches `n` or more occurrences
`{n,m}`	Matches between `n` and `m` occurrences
`\`	Escapes special characters

Character Classes

Pattern	Description
`[abc]`	Matches `a`, `b`, or `c`
`[^abc]`	Matches any character except `a`, `b`, or `c`
`[a-z]`	Matches any lowercase letter
`[A-Z]`	Matches any uppercase letter
`[0-9]`	Matches any digit
`\d`	Matches any digit (same as `[0-9]`)
`\D`	Matches any non-digit
`\w`	Matches any word character (letters, numbers, underscore)
`\W`	Matches any non-word character
`\s`	Matches any whitespace (spaces, tabs, newlines)
`\S`	Matches any non-whitespace

Groups & References

Pattern	Description
`(abc)`	Capturing group
`(?:abc)`	Non-capturing group
`\1`, `\2`	Backreferences to captured groups
`(?<name>abc)`	Named capturing group
`\k<name>`	Reference to named group

Assertions & Anchors

Pattern	Description
`^`	Start of line
`$`	End of line
`\b`	Word boundary
`\B`	Not a word boundary
`(?=abc)`	Positive lookahead
`(?!abc)`	Negative lookahead
`(?<=abc)`	Positive lookbehind (not all regex engines support this)
`(?<!abc)`	Negative lookbehind

Special Obsidian Use Cases

Pattern	Description
`\[\[.*?\]\]`	Matches Obsidian wiki-style links `[[Link]]`
`!\[.?\]$.?$`	Matches embedded images `![](image.png)`
`#\w+`	Matches a hashtag `#tag`
`- \[ \]`	Matches an empty checkbox `- [ ]`
`- \[x\]`	Matches a completed checkbox `- [x]`

Examples

Regex	Matches
`\d{4}-\d{2}-\d{2}`	Dates in `YYYY-MM-DD` format
`#[a-zA-Z0-9_-]+`	Obsidian tags
`!\[.?\]$.?$`	Embedded images
`\[\[(.*?)\]\]`	Wiki links and captures link text

This sheet should help with most regex-related tasks in Obsidian, whether searching, replacing, or structuring notes!

graph TD
    subgraph Encoder
        direction TB
        A[Input Embedding] --> B(Positional Encoding);
        B --> C{Multi-Head<br>Attention};
        C --> D(Add & Norm);
        D --> E{Feed Forward};
        E --> F(Add & Norm);
        F --> G((Encoder Output));
    end

    subgraph Decoder
        direction TB
        H[Output Embedding] --> I(Positional Encoding);
        I --> J{Masked Multi-Head<br>Attention};
        J --> K(Add & Norm);
        G --> L{Multi-Head<br>Attention};
        K --> L;
        L --> M(Add & Norm);
        M --> N{Feed Forward};
        N --> O(Add & Norm);
    end
    
    O --> P[Linear];
    P --> Q[Softmax];
    Q --> R((Final Output Probabilities));

    style A fill:#f9f,stroke:#333,stroke-width:2px
    style H fill:#f9f,stroke:#333,stroke-width:2px
    style R fill:#ccf,stroke:#333,stroke-width:2px
    style G fill:#ccf,stroke:#333,stroke-width:2px

Graph View