Usage

1. Implement Table trait for your custom type by defining the row method which returns the type as a Vec<String>.

2. Create a Veg struct with a header definition based on a Markdown table header.

3. Use the Veg struct like a Vec to gather instances of your type.

4. Call one of the following methods to generate a table:

   • markdown: Markdown table using the initial header definition
   • markdown_with: Markdown table using a custom header definition and/or column indexes

Example

// Import Veg
# use anyhow::anyhow;
use veg::Veg;

// Create a custom type
struct Point {
    x: f32,
    y: f32,
}

// Implement a method that creates a Box of the custom type
impl Point {
    fn new(x: f32, y: f32) -> Box<Point> {
        Box::new(Point { x, y })
    }
}

// Implement the veg::Table::row method to define how to print the custom type
impl veg::Table for Point {
    fn row(&self) -> Vec<String> {
        // Add `$` for inline LaTeX math spans
        [self.x, self.y].iter().map(|x| format!("${x}$")).collect()

        // Other ideas:
        //
        // - Add 3 decimal places:
        //
        // [self.x, self.y].iter().map(|x| format!("${x:.3}$")).collect()
        //
        // - Do something different for x and y:
        //
        // vec![
        //     format!("${:.1}$", self.x),
        //     format!("${:.4}$", self.y),
        // ]
        //
        // - Just convert to string:
        //
        // [self.x, self.y].iter().map(|x| x.to_string())).collect()
        //
        // ...
    }
}

// Create a Veg via the table method with a header definition
let mut v = Veg::table("$x$|$y$\n-:|-:");

// Add a single point
v.push(Point::new(1.0, 1.0));

// Add a bunch of points
v.append(&mut vec![
    Point::new(2.0, 4.0),
    Point::new(3.0, 9.0),
    Point::new(4.0, 16.0),
]);

// Render as a markdown table
assert_eq!(
    v.markdown().unwrap(),
    "\
| $x$ |  $y$ |
|----:|-----:|
| $1$ |  $1$ |
| $2$ |  $4$ |
| $3$ |  $9$ |
| $4$ | $16$ |
\
    ",
);

// Render as a markdown table with a modified header definition
assert_eq!(
    v.markdown_with(Some("X|Y\n-|-"), None).unwrap(),
    "\
| X   | Y    |
|-----|------|
| $1$ | $1$  |
| $2$ | $4$  |
| $3$ | $9$  |
| $4$ | $16$ |
\
    ",
);

// Render as a markdown table with a modified header definition to increase the
// column widths
assert_eq!(
    v.markdown_with(Some("X|Y\n------|------"), None).unwrap(),
    "\
| X      | Y      |
|--------|--------|
| $1$    | $1$    |
| $2$    | $4$    |
| $3$    | $9$    |
| $4$    | $16$   |
\
    ",
);

// Just render the second column
assert_eq!(
    v.markdown_with(None, Some(&[1])).unwrap(),
    "\
|  $y$ |
|-----:|
|  $1$ |
|  $4$ |
|  $9$ |
| $16$ |
\
    ",
);

// Reorder the columns
assert_eq!(
    v.markdown_with(None, Some(&[1, 0])).unwrap(),
    "\
|  $y$ | $x$ |
|-----:|----:|
|  $1$ | $1$ |
|  $4$ | $2$ |
|  $9$ | $3$ |
| $16$ | $4$ |
\
    ",
);

// Duplicate column `y`
assert_eq!(
    v.markdown_with(None, Some(&[0, 1, 1])).unwrap(),
    "\
| $x$ |  $y$ |  $y$ |
|----:|-----:|-----:|
| $1$ |  $1$ |  $1$ |
| $2$ |  $4$ |  $4$ |
| $3$ |  $9$ |  $9$ |
| $4$ | $16$ | $16$ |
\
    ",
);

// Try to give invalid column indexes
assert_eq!(
    v.markdown_with(None, Some(&[3, 2, 0, 1])).unwrap_err().to_string(),
    "Invalid column indexes: 2, 3",
);

Features

colored

The colored feature enables the veg::colored module which provides the same API, but uses the colored crate to colorize Veg tables for printing to the terminal.

See tests/colored.rs and/or run cargo test --features colored --test colored -- --nocapture.

Changelog

• 0.1.0 (2023-12-11): Initial release
  • 0.1.1 (2023-12-11): Add makefile, changelog; fix readme, clippy
• 0.2.0 (2023-12-11): Convert the table function to a method
  • 0.2.1 (2023-12-11): Fix readme
• 0.3.0 (2023-12-12): Enable single column tables; add the markdown_with method to enable column subsets, reordering, duplicating, and temporary headers; add examples to the module doctest
• 0.4.0 (2023-12-16): Add colored feature/module enabling terminal colors via the colored crate
  • 0.4.1 (2023-12-16): Fix changelog
  • 0.4.2 (2023-12-17): Improve readme, doc, and tests
  • 0.4.3 (2023-12-17): Add doc for colored module; make the colored png smaller; improve doc
  • 0.4.4 (2023-12-17): Fix colored module doc
  • 0.4.5 (2023-12-17): Fix doc
  • 0.4.6 (2023-12-18): Fix veg::colored::Veg::table argument type
  • 0.4.7 (2023-12-18): Add Veg::is_empty methods
  • 0.4.8 (2024-01-06): Fix empty string find unwrap issue; update dependencies
• 0.5.0 (2024-03-10): Fix Unicode text width algorithm; update dependencies
  • 0.5.1 (2024-07-26): Fix makefile; update dependencies
  • 0.5.2 (2024-10-18): Update dependencies
  • 0.5.3 (2024-10-24): Update dependencies
  • 0.5.4 (2024-12-04): Update dependencies; add commit target to makefile
  • 0.5.5 (2025-02-20): Update dependencies
  • 0.5.6 (2025-04-16): Update dependencies
• 0.6.0 (2025-08-27): Update dependencies; 2024 edition
  • 0.6.1 (2025-10-26): Update dependencies
  • 0.6.2 (2025-11-11): Update dependencies (none); cargo fmt
  • 0.6.3 (2025-11-13): Update dependencies (none); clippy fixes