Beautiful, aligned table output for Ruby hashes and objects with zero dependencies.

• 🚀 Zero runtime dependencies
• 📊 Automatic column width calculation
• 🎯 Smart type formatting (booleans, nil, strings)
• 📐 Column alignment (left, right, center)
• 🎨 Custom column headers
• 🔍 Column filtering
• 📝 Preserves original column order
• 📄 Markdown table output (v0.2.0+)
• 🌈 Optional color output via pastel gem (v0.3.0+)
• 📤 CSV export with Excel-compatible encoding (v0.4.0+)

Add this line to your application's Gemfile:

gem 'typed_print'

Or install it yourself:

gem install typed_print

require 'typed_print'

data = [
  { name: "Alice", score: 100, active: true },
  { name: "Bob", score: 42, active: false }
]

TypedPrint.print(data)

Output:

Name  Score Active 
------+------+-------
Alice   100 true   
Bob      42 false  

TypedPrint.print(data, format: :markdown)

Output:

| Name  | Score | Active |
|-------|-------|--------|
| Alice | 100   | true   |
| Bob   | 42    | false  |

TypedPrint.print(data, align: { score: :right })

Output:

Name  Score Active 
------+------+-------
Alice   100 true   
Bob      42 false

TypedPrint.print(data, only: [:name, :score])

Output:

Name  Score 
------+------
Alice   100 
Bob      42 

TypedPrint.print(data, headers: { name: "Username", score: "Points", active: "Status" })

Output:

Username Points Status 
---------+------+-------
Alice       100 true   
Bob          42 false  

table_string = TypedPrint.table(data)
puts table_string.upcase

# Markdown format
markdown_string = TypedPrint.table(data, format: :markdown)
File.write("table.md", markdown_string)

mixed_data = [
  { name: "Product A", price: 29.99, in_stock: true, notes: nil },
  { name: "Product B", price: 49.99, in_stock: false, notes: "Limited edition" }
]

TypedPrint.print(mixed_data)

Output:

Name      Price In_stock Notes        
----------+-------+---------+-------------
Product A   29.99 true                  
Product B   49.99 false    Limited edition

TypedPrint.print(data, options) Prints the formatted table to stdout and returns nil.

Options:

• align: Hash - Column alignment (:left, :right, :center), defaults to :left
• only: Array - Array of column symbols to display
• headers: Hash - Custom headers for columns
• format: Symbol - Output format (:plain or :markdown), defaults to :plain
• color: Boolean - Auto color by type (headers cyan, numbers/true green, false red, nil gray), requires pastel gem
• colors: Hash - Manual per-column color map (e.g. { name: :cyan, score: :green }), requires pastel gem

TypedPrint.table(data, options) returns the formatted table as a string.

Same options as print.

TypedPrint.to_csv(data, options) returns data as a CSV string.

Options:

• only: Array - Columns to include
• headers: Hash - Custom column headers
• delimiter: String - Column separator (default: ",")

TypedPrint.save(data, path, options) writes a CSV file with UTF-8 BOM and returns nil.

Same options as to_csv.

Color support is optional and requires the pastel gem. Add it to your Gemfile:

gem 'pastel'

Automatic coloring by type:

TypedPrint.print(data, color: true)
# Headers → cyan, Integer/Float/true → green, false → red, nil → gray

Manual per-column colors:

TypedPrint.print(data, colors: { name: :cyan, score: :green, active: :yellow })

Both :plain and :markdown formats support color. If pastel is not installed, color options are silently ignored and output is plain text.

No extra dependencies — uses Ruby's stdlib csv.

Return CSV string:

csv = TypedPrint.to_csv(data)
# => "Name,Score,Active\nAlice,100,true\nBob,42,false\n"

Save to file (Excel-compatible UTF-8 BOM):

TypedPrint.save(data, "output.csv")

Custom delimiter:

TypedPrint.to_csv(data, delimiter: ";")
TypedPrint.save(data, "output.csv", delimiter: ";")

Filter columns and custom headers:

TypedPrint.to_csv(data, only: [:name, :score], headers: { score: "Points" })

After checking out the repo, run bin/setup to install dependencies. Then, run rake test to run the tests.

To install this gem onto your local machine, run bundle exec rake install.

Bug reports and pull requests are welcome on GitHub at https://github.com/yourusername/typed_print.

The gem is available as open source under the terms of the MIT License.