tea/vendor/github.com/muesli/termenv/README.md

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<p align="center">
<img src="https://stuff.charm.sh/termenv.png" width="480" alt="termenv Logo">
<br />
<a href="https://github.com/muesli/termenv/releases"><img src="https://img.shields.io/github/release/muesli/termenv.svg" alt="Latest Release"></a>
<a href="https://godoc.org/github.com/muesli/termenv"><img src="https://godoc.org/github.com/golang/gddo?status.svg" alt="GoDoc"></a>
<a href="https://github.com/muesli/termenv/actions"><img src="https://github.com/muesli/termenv/workflows/build/badge.svg" alt="Build Status"></a>
<a href="https://coveralls.io/github/muesli/termenv?branch=master"><img src="https://coveralls.io/repos/github/muesli/termenv/badge.svg?branch=master" alt="Coverage Status"></a>
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</p>
`termenv` lets you safely use advanced styling options on the terminal. It
gathers information about the terminal environment in terms of its ANSI & color
support and offers you convenient methods to colorize and style your output,
without you having to deal with all kinds of weird ANSI escape sequences and
color conversions.
![Example output](https://github.com/muesli/termenv/raw/master/examples/hello-world/hello-world.png)
## Installation
```bash
go get github.com/muesli/termenv
```
## Query Terminal Status
```go
// returns supported color profile: Ascii, ANSI, ANSI256, or TrueColor
termenv.ColorProfile()
// returns default foreground color
termenv.ForegroundColor()
// returns default background color
termenv.BackgroundColor()
// returns whether terminal uses a dark-ish background
termenv.HasDarkBackground()
```
## Colors
`termenv` supports multiple color profiles: ANSI (16 colors), ANSI Extended
(256 colors), and TrueColor (24-bit RGB). Colors will automatically be degraded
to the best matching available color in the desired profile:
`TrueColor` => `ANSI 256 Colors` => `ANSI 16 Colors` => `Ascii`
```go
out := termenv.String("Hello World")
// retrieve color profile supported by terminal
p := termenv.ColorProfile()
// supports hex values
// will automatically degrade colors on terminals not supporting RGB
out = out.Foreground(p.Color("#abcdef"))
// but also supports ANSI colors (0-255)
out = out.Background(p.Color("69"))
fmt.Println(out)
```
## Styles
```go
out := termenv.String("foobar")
// text styles
out.Bold()
out.Faint()
out.Italic()
out.CrossOut()
out.Underline()
out.Overline()
// reverse swaps current fore- & background colors
out.Reverse()
// blinking text
out.Blink()
// combine multiple options
out.Bold().Underline()
```
## Template Helpers
```go
// load template helpers
f := termenv.TemplateFuncs(termenv.ColorProfile())
tpl := template.New("tpl").Funcs(f)
// apply bold style in a template
bold := `{{ Bold "Hello World" }}`
// examples for colorized templates
col := `{{ Color "#ff0000" "#0000ff" "Red on Blue" }}`
fg := `{{ Foreground "#ff0000" "Red Foreground" }}`
bg := `{{ Background "#0000ff" "Blue Background" }}`
// wrap styles
wrap := `{{ Bold (Underline "Hello World") }}`
// parse and render
tpl = tpl.Parse(bold)
var buf bytes.Buffer
tpl.Execute(&buf, nil)
fmt.Println(buf)
```
Other available helper functions are: `Faint`, `Italic`, `CrossOut`,
`Underline`, `Overline`, `Reverse`, and `Blink`.
## Screen
```go
// Reset the terminal to its default style, removing any active styles
termenv.Reset()
// Switch to the altscreen. The former view can be restored with ExitAltScreen()
termenv.AltScreen()
// Exit the altscreen and return to the former terminal view
termenv.ExitAltScreen()
// Clear the visible portion of the terminal
termenv.ClearScreen()
// Move the cursor to a given position
termenv.MoveCursor(row, column)
// Hide the cursor
termenv.HideCursor()
// Show the cursor
termenv.ShowCursor()
// Move the cursor up a given number of lines
termenv.CursorUp(n)
// Move the cursor down a given number of lines
termenv.CursorDown(n)
// Move the cursor down a given number of lines and place it at the beginning
// of the line
termenv.CursorNextLine(n)
// Move the cursor up a given number of lines and place it at the beginning of
// the line
termenv.CursorPrevLine(n)
// Clear the current line
termenv.ClearLine()
// Clear a given number of lines
termenv.ClearLines(n)
```
## Color Chart
![ANSI color chart](https://github.com/muesli/termenv/raw/master/examples/color-chart/color-chart.png)
You can find the source code used to create this chart in `termenv`'s examples.
## Related Projects
Check out [Glow](https://github.com/charmbracelet/glow), a markdown renderer for
the command-line, which uses `termenv`.
## License
[MIT](https://github.com/muesli/termenv/raw/master/LICENSE)