Terminal Styling

Tint provides a fluent API for styling terminal text with colors and modifiers.

Basic Usage

import wvlet.uni.cli.Tint

// Single color
println(Tint.red("Error message"))
println(Tint.green("Success!"))
println(Tint.blue("Information"))

// With modifiers
println(Tint.red.bold("Bold red"))
println(Tint.yellow.underline("Underlined"))
println(Tint.cyan.italic("Italic text"))

Colors

Foreground Colors

Tint.black("text")
Tint.red("text")
Tint.green("text")
Tint.yellow("text")
Tint.blue("text")
Tint.magenta("text")
Tint.cyan("text")
Tint.white("text")
Tint.gray("text")

Bright Colors

Tint.brightRed("text")
Tint.brightGreen("text")
Tint.brightYellow("text")
Tint.brightBlue("text")
Tint.brightMagenta("text")
Tint.brightCyan("text")
Tint.brightWhite("text")

Background Colors

Tint.bgRed("text")
Tint.bgGreen("text")
Tint.bgYellow("text")
Tint.bgBlue("text")
Tint.bgMagenta("text")
Tint.bgCyan("text")
Tint.bgWhite("text")

Text Modifiers

Tint.bold("Bold text")
Tint.dim("Dimmed text")
Tint.italic("Italic text")
Tint.underline("Underlined text")
Tint.strikethrough("Strikethrough")
Tint.inverse("Inverted colors")
Tint.hidden("Hidden text")

Chaining Styles

Combine multiple styles:

Tint.red.bold("Red and bold")
Tint.green.underline("Green underlined")
Tint.yellow.bgBlue.bold("Yellow on blue, bold")
Tint.cyan.italic.underline("Cyan italic underlined")

Extended Colors

RGB Colors

Tint.rgb(255, 87, 51)("Custom RGB")
Tint.bgRgb(100, 149, 237)("Custom background")

Hex Colors

Tint.hex("#FF5733")("Orange-red")
Tint.hex("#00FF00")("Lime green")
Tint.bgHex("#663399")("Purple background")

256-Color Palette

Tint.ansi256(208)("Color 208")
Tint.bgAnsi256(57)("Background 57")

Reusable Styles

Create style presets:

val errorStyle = Tint.red.bold
val successStyle = Tint.green
val warningStyle = Tint.yellow.bold
val infoStyle = Tint.cyan

println(errorStyle("Failed to connect"))
println(successStyle("Operation completed"))
println(warningStyle("Disk space low"))
println(infoStyle("Processing..."))

Disabling Colors

For non-TTY output or CI environments:

val style = Tint.red.bold

// Disable for this style
val plain = style.noColor
println(plain("No colors"))

// Or conditionally
val isInteractive = System.console() != null
val tint = if isInteractive then Tint.red else Tint().noColor

Example: CLI Output

import wvlet.uni.cli.Tint

object MyCLI:
  val error = Tint.red.bold
  val success = Tint.green
  val highlight = Tint.cyan.bold
  val dim = Tint.gray

  def printStatus(name: String, status: String, ok: Boolean): Unit =
    val statusStyle = if ok then success else error
    val symbol = if ok then "✓" else "✗"
    println(s"${dim("[")}${statusStyle(symbol)}${dim("]")} ${name}: ${statusStyle(status)}")

  def main(args: Array[String]): Unit =
    printStatus("Database", "Connected", true)
    printStatus("Cache", "Timeout", false)
    printStatus("API", "Ready", true)

Output:

[✓] Database: Connected
[✗] Cache: Timeout
[✓] API: Ready

Best Practices

1. Define styles once and reuse them
2. Detect terminal support before using colors
3. Provide plain fallback for non-TTY environments
4. Use semantic names (errorStyle, not redBold)
5. Keep it readable - don't overuse colors