Color String

This lib is usable for console (terminal) apps when you need to manage strings with color codes.

I also have goterm that is a functions pack for console apps.
Also I recommend you to use Guffers for a more complex CLI development.

Why colorstrings?

I prefer to show you...

The problem it fixes:

// Putting a \033[0m after 'hi'

/* --- Without colorstrings --- */

str := " \033[31mHey \033[1mhi! "
str = str[:7] + "\033[0m" + str[7:]   // ✗ ' \e[31mH\e[0mey \e[1mhi! '
str = str[:16] + "\033[0m" + str[16:] // ✔ ' \e[31mHey \e[1mhi\e[0m! '


/* --- With colorstrings --- */

str, _ := NewColorString(" \033[31mHey \033[1mhi! ")
str.Colorize("0", 7)
str.Join() // Get the result

// ✔ ' \e[31mHey \e[1mhi\e[0m! '

What is the problem, and how it fixes it:

/*
 * in a pure string:
 *   ' Hey hi! '
 *           ^ 7
 *
 * in a colored string:
 *   ' \033[31mHey \033[1mhi! '
 *           ^ 7            ^ 16
 *
 * Colorstrings keep the positions.
 */

How to set up

Run this code in your terminal inside your project directory:

$ go get -u github.com/pandasoli/colorstrings

And put this in your code:

import . "github.com/pandasoli/colorstrings"

BTW: If you miss some features, please make an issue and I'll reply you as soon as possible.

Initialize from an existing string

You don't have to create a new pure string (without colors), we can use a string already with them.

str, err := NewColorString("  \033[1;31mHey hi, man!\033[0m")
if err != nil { panic(err) }

An error will be returned if found an unparsable color.
PS: This lib doesn't recognize position codes!

To initialize a new pure string use the same function.
If it's really pure you won't need the err return.

Warnings

Joining colors

An important thing to say is that this library makes only one color by position, when you try to put a color in a position that there's already a color, they will be "joined".

So \033[31m\033[42m is impossible.
The library is gonna try to join them like this \033[31;42m.

Maybe I am gonna change it, but not yet for now.

No duplicates

A color cannot have more than one background or foreground colors.

I mean \033[31;94m is impossible.
The lib is gonna make the last one the only one: \033[94m.

Features

Colorize(str_fields string, position uint) error

/* Add a new color to the string at the position
Ex: str.Colorize("1;38;5;200", 2) */

It returns an error if:

• the position is bigger than the string
• a field cannot be parsed
• a field non-RGB is bigger than 107
• a field that doesn't expect props has some
• no more fields after 38, 48 or 58
• missing fields in 8-bit or RGB color

Join() string

// Join the string with its colors

Substring(position, length uint) (res ColorString, err error)

// Cut the string from the position to position + length

Append(strs ...ColorString)

// Append another string at the end of the main one

Remove(position, length uint) error

// Remove a piece of the string

This is gonna return an error if position is bigger than the string.

Connect(str ColorString, position uint) error

// Replaces from the position to the length of the str with the str

This is gonna return an error if the str is bigger the current string,
or the position + the str's length is bigger than the current string.

AppendAt(str ColorString, position uint) error

// Append another string inside the main one at the told position

This returns an error if position is bigger than the string.

Clear()

// Clear the string and the colors

SplitString(at string) (res []colorstring, pos []uint)

/* Split the main string based on the piece of string passed and returns
the parts where the piece was in the middle, and
the positions where pieces were found */

Credits

Gopher icons by Egon Elbre
Look at the Dev Notes if you would like to contribute!