Rhai extensions

Besides the basic Rhai features, these are the modules/behaviors defined:

Variables with the `variable` module

get/set

variable::is_set(name: &str) -> bool

Returns true if the variable/placeholder has been set for the template
variable::get(name: &str) -> value

Gets any defined variable in the Liquid template object
variable::set(name: &str, value: (&str|bool))

Set new or overwrite existing variables. Do not allow to change types. Note that you can set entire arrays with this (e.g. variable::set("array",["a","b"])) but not individual elements (variable::set("array[1]","a") will not work).

Prompt for values with `variable::prompt`

variable::prompt(text: &str, default_value: bool) -> value

Prompt the user for a boolean value
variable::prompt(text: &str) -> value

Prompt the user for a string value
variable::prompt(text: &str, default_value: &str) -> value

Prompt the user for a string value, with a default already in place
variable::prompt(text: &str, default_value: &str, regex: &str) -> value

Prompt the user for a string value, validated with a regex
variable::prompt(text: &str, default_value: &str, choices: Array) -> value

Prompt the user for a choice value

Files with the `file` module

file::exists(path: &str)

Test if a path exists
file::rename(from: &str, to: &str)

Rename one of the files in the template folder
file::delete(path: &str)

Delete a file or folder inside the template folder
file::write(file: &str, content: &str)

Create/overwrite a file inside the template folder
file::write(file: &str, content: Array)

Create/overwrite a file inside the template folder, each entry in the array on a new line

file::listdir(path = ".") -> Array<String>

List the contents of a directory

Note: The path is relative to the template folder, and cannot be outside the template folder.

Examples:

let files = file::listdir();
for f in files {
    print(`file: ${f}`);
}

// this is actually the same as above, the path must be inside the template directory, cannot be absolute or ourside
let files = file::listdir(".");
for f in files {
    print(`file: ${f}`);
}

The `system` module

system::command(cmd: &str, args: Array = []) -> value

Execute a command on the system generating the project from a template.

The user will be prompted with
```
The template is requesting to run the following command. Do you agree?
<command> <args>
```
unless the user uses the flag --allow-commands. If the user attempts to use the --silent flag without the --allow-commands flag will fail.

Examples:
```
// this returns the PWD as a string
let pwd = system::command("pwd");

// but this works too and does the same
system::command("pwd", []);

// this will cat a file and returns the content
let content = system::command("cat", ["file.txt"]);
```
See also: the many-hooks-in-action example project
system::date() -> Date

Get the date in UTC from the system as an object with the properties year, month, and day.

The `env` module

The env module provides access to environment variables.

env::working_directory

Returns the current working directory as a string. This is the directory where the cargo-generate pre-processes the template, before it is copied over to the users destination directory.

Examples:
```
let wd = env::working_directory;
print(`Working directory: ${wd}`);
```
See also: the many-hooks-in-action example project
env::destination_directory

Returns the destination directory as a string. This is the directory where the template is copied to, and where the user will find the generated project.

Examples:
```
let dd = env::destination_directory;
print(`Destination directory: ${dd}`);
```

Other

abort(reason: &str): Aborts cargo-generate with a script error.

Changing case of strings

to_kebab_case(str: &str) -> String

"We are going to inherit the earth." => "we-are-going-to-inherit-the-earth"
to_lower_camel_case(str: &str) -> String

"It is we who built these palaces and cities." => "itIsWeWhoBuiltThesePalacesAndCities"
to_pascal_case(str: &str) -> String

Same as to_upper_camel_case(str: &str) -> String
to_shouty_kebab_case(str: &str) -> String

"We are going to inherit the earth." => "WE-ARE-GOING-TO-INHERIT-THE-EARTH"
to_shouty_snake_case(str: &str) -> String

"That world is growing in this minute." => "THAT_WORLD_IS_GROWING_IN_THIS_MINUTE"
to_snake_case(str: &str) -> String

"We carry a new world here, in our hearts." => "we_carry_a_new_world_here_in_our_hearts"
to_title_case(str: &str) -> String

"We have always lived in slums and holes in the wall." => "We Have Always Lived In Slums And Holes In The Wall"
to_upper_camel_case(str: &str) -> String

"We are not in the least afraid of ruins." => "WeAreNotInTheLeastAfraidOfRuins"