Standard Library

Hush‘s standard library is available through the std global variable, which is implicitly available to all scripts. It is nothing but a dictionary of predefined functions, which can be used like any other user defined functions.

Currently, the following functions are available:

std.args()

Gets an array of command line arguments.

std.assert(value)

Asserts that value is true, panics otherwise.

std.bind(obj, function)

Returns a new function that binds function to obj, so that self will always refer to obj when the function is called.

std.catch(function)

Runs the given function, and returns an error if it panics. This should be used sparingly, as panics shouldn’t be used for recoverable errors.

std.cd(dir)

Change the current directory to dir.

std.contains(collection, value)

Checks if collection contains an item that is equal to value. May be used with strings, arrays and dicts.

std.cwd()

Returns the current working directory.

std.env(key)

Gets the value of the environment variable key, or nil if it’s not defined.

std.error(description, context)

Create a new error with the given description and context. The description must be a string.

std.export(key, value)

Set the environment variable key to value. Both arguments must be strings.

std.float(value)

Convert value to float. Accepts string, int and float.

std.glob(path)

Expands the given path in the current directory, using the shell expansion rules (*, %, etc).

std.has_error(value)

Recursively checks if value contains a value of type error.

std.import(path)

Load the Hush script from the given path, relative to the current file.

std.int(value)

Convert value to int. Accepts string, int and float.

std.is_empty(collection)

Checks if the given collection is empty. Accepts strings, arrays and dicts.

std.iter(collection)

Returns an iterator function for the given collection. Accepts strings, arrays and dicts.

std.json.dump(value)

Convert the given value to a JSON string. Panics if value contains a value that cannot be serialized as JSON (function or error).

std.json.parse(string)

Parse the given json string. Returns an error if parsing fails.

std.len(collection)

Returns the amount of elements in the given collection. Accepts strings, arrays and dicts.

std.panic(value)

Panics with the given value as description.

std.pop(array)

Removes the last element from the given array, returning it. Panics if the array is empty.

std.print(value)

Prints the given value to stdout, including a newline.

std.push(array, value)

Adds the given value to the end of array.

std.range(from, to, step)

Returns an iterator function that yields numbers in the given range.

std.read(prompt)

Read a line from stdin, using the given prompt, which must be a string.

std.regex(pattern)

Build a regex object from pattern, which must be a string. If pattern is not a valid regex, an error will be returned. Otherwise, returns a dict with the following methods:

• match(string): returns a bool indicating whether the pattern matches the given string.
• split(string): splits string using the pattern, returning an array of strings.
• replace(string, replace): returns a string with replaced occurrences of pattern in string. replace must be a string.

std.replace(string, seach, replace)

Replace occurrences of search with replace in string. All parameters must be strings.

std.sleep(ms)

Sleep for the given amount of milliseconds. Accepts positive integers only.

std.sort(array)

Sorts the given array.

std.split(string, pattern)

Splits the given string by occurrences of pattern, returning a non-empty array. Both arguments must be strings.

std.substr(string, from, length)

Slice the given string. The two last parameters must be positive integers.

std.to_string(value)

Converts the given value to string.

std.trim(string)

Removes whitespace from the start and end of the given string.

std.typecheck(value, type)

Checks if the given value has type type, panics otherwise. type must be a string.

std.try_typecheck(value, type)

Checks if the given value has type type, returns an error otherwise. type must be a string.

std.type(value)

Returns a string describing the type of value: "nil", "bool", "char", "int", "float", "string", "array", "dict", "function", or "error".