[](https://github.com/lizmat/String-Color/actions)
NAME
====
String::Color - map strings to a color code
SYNOPSIS
========
```raku
use String::Color;
use Randomcolor; # some module for randomly generating colors
my $sc = String::Color.new(
generator => { Randomcolor.new.list.head },
cleaner => { .lc }, # optionally provide own cleaning logic
colors => %colors-so-far, # optionally start with given set
);
my @added = $sc.add(@nicks); # add mapping for strings in @nicks
my %colors := $sc.Map; # set up hash with color mappings so far
say "$color is already used"
if $sc.known($color); # check if a color is used already
```
DESCRIPTION
===========
String::Color provides a class and logic to map strings to a (random) color code. It does so by matching the cleaned version of a string.
The way a color is generated, is determined by the required `generator` named argument: it should provice a `Callable` that will take a cleaned string, and return a color for it.
The way a string is cleaned, can be specified with the optional `cleaner` named argument: it should provide a `Callable` that will take the string, and return a cleaned version of it. By default, the cleaning logic will remove any non-alpha characters, and lowercase the resulting string.
Strings can be continuously added by calling the `add` method. The current state can be obtained with the `Map` method. The `known` method can be used to see whether a color is already being used or not.
Note that colors are described as strings. In whichever format you would like. Technically, this module could be used to match strings to other strings that would not necessarily correspond to colors. But that's entirely up to the fantasy of the user of this module.
Also note that by e.g. writing out the `Map` of a `String::Color` object as e.g. **JSON** to disk, and then later use that in the `colors` argument to `new`, would effectively make the mapping persistent.
Finally, even though this may look like a normal hash, it is different in two ways: the keys (the `strings` method) are always returned in alphabetical order, and all operations are thread safe (although results may be out of date).
CLASS METHODS
=============
new
---
```raku
my $sc = String::Color.new(
generator => -> $string {
$string eq 'liz'
?? "ff0000"
!! RandomColor.new.list.head
},
cleaner => { .lc }, # optionally provide own cleaning logic
colors => %colors-so-far, # optionally start with given set
);
```
The `new` class method takes two named arguments.
### :cleaner
The `cleaner` named argument allows one to specify a `Callable` which is supposed to take a string, and return a cleaned version of the string. By default, a cleaner that will remove all non-alpha characters and return the resulting string in lowercase, will be used.
### :colors
The `colors` named argument allows one to specify a `Hash` / `Map` with colors that have been assigned to strings so far. Only the empty string mapping to the empty string will be assumed, if not specified.
### :generator
The `generator` named argument specifies a `Callable` that will be called to generate a colors for the associated string (which gets passed to the `Callable`). It **must** be specified.
INSTANCE METHODS
================
add
---
```raku
my @added = $sc.add(@strings);
```
The `add` instance method allows adding of strings to the colors mapping. It takes a list of strings as the positional argument.
It returns an array of `Pair`s (where the key is the string, and the value is the color) that were actually added.
cleaned
-------
```raku
.say for $sc.cleaned;
```
The `cleaned` instance method returns the cleaned strings in the same order as `strings`.
colors
------
```raku
say "colors assigned:";
.say for $sc.colors.unique;
```
The `colors` instance method returns the colors in the same order as `strings`.
elems
-----
```raku
say "$sc.elems() mappings so far";
```
The `elems` instance method returns the number of mappings.
known
-----
```raku
say "$color is already used"
if $sc.known($color); # check if a color is used already
```
The `known` instance method takes a single string for color, and returns whether that color is already in use or not.
Map
---
```raku
my %colors := $sc.Map; # create simple Associative interface
$file.IO.spurt: to-json $sc.Map; # make mapping persistent
my %mapped := $sc.Map: -> $string, $color {
"$string"
}
```
The `Map` instance method returns the state of the mapping as a `Map` object, which can be bound to create an `Associative` interface. Or it can be used to create a persistent version of the mapping.
It can also take an optional `Callable` parameter to indicate mapping logic that should be applied: this `Callable` will be called with two positional arguments: the string, and the associated color. It should return a `Str` that should be associated with the string.
strings
-------
```raku
say "strings mapped:";
.say for $sc.strings;
```
The `strings` instance method returns the strings in alphabetical order.
AUTHOR
======
Elizabeth Mattijsen
Source can be located at: https://github.com/lizmat/String-Color . Comments and Pull Requests are welcome.
COPYRIGHT AND LICENSE
=====================
Copyright 2021 Elizabeth Mattijsen
This library is free software; you can redistribute it and/or modify it under the Artistic License 2.0.