ListUtil
In Mini Micro, listUtil is an import module in the /sys/lib directory. It provides various additional list-related functions, many of them directly extending the list datatype.
Like all the modules in /sys/lib, the best documentation for listUtil is the source code (/sys/lib/listUtil.ms) itself. But this page summarizes the content in more concise form.
Added list methods
The following methods are added to the list type, and so are accessed using dot syntax after any list, for example: [1, 2, 3].reverse
Some of these methods mutate (modify) the list you call it on; others return a new list. See below, or the header comments in the source code, for details. Note that this is different from stringUtil, where all methods return a new string (since strings are immutable).
| Method | Returns |
|---|---|
| contains(item) | true if this list contains the given item |
| lastIndexOf(element, beforeIdx=null) | returns the *last* index of the given element, optionally before a given index. Returns null if not found. |
| split(delimiter, maxCount=null) | similar to string.split, this splits a list into sub-lists by where the given delimiter element is found. |
| deepCopy | returns a clone of this list, recursively cloning any sub-lists as well |
| add(addend) | mutates this list by adding elements of another list of the same size, or by adding addend to all elements |
| plus(addend) | same as add, but returns a new list, leaving this list unchanged
|
| multiplyBy(factor) | mutates this list by multiplying elements of another list of the same size, or by multiplying all elements by factor |
| times(addend) | same as multiplyBy, but returns a new list, leaving this list unchanged
|
| dot(other) | returns sum of pairwise products of elements in this list and other |
| reverse | mutates this list by reversing the order of its elements |
| reversed | returns a new list containing the elements of this one in reverse order, leaving this list unchanged |
| apply(func) | mutates this list by applying a function to every element, in place |
| apply1(func, arg) | same as apply, but takes one extra argument
|
| applied(func) | same as apply but returns a new list |
| applied1(func, arg) | same as apply1 but returns a new list |
| mean | returns the average (sum divided by number of values) of this list |
| counts | returns a map that maps each unique element of this list, to the number of times that value occurs |
| distinct | returns a list of the unique values in this list (in arbitrary order) |
| product | returns the result of multiplying together all the elements in this list |
| min | returns the minimum value in this list |
| max | returns the maximum value in this list |
| reduce(func) | reduce the list to a single value by applying func to two values at a time |
| filter(func) | mutates this list by removing all elements x where func(x) is not true;
or where x.func is not true (if func is actually a string) |
| filter1(func, arg) | same as filter but takes one extra argument. |
| filtered(func) | same as filter, but returns a new list, leaving this list unchanged |
| filtered1(func, arg) | same as filtered but takes one extra argument. |
| compress(valueToCompress) | replace each run of a given value with a single instance of that value (in place). |
| compressed(valueToCompress) | same as compress' but returns a new list. |
| valuesOf(indexToExtract) | returns a list containing elem[indexToExtract] for every element elem |
| removeVal(val, removeAll=false) | mutates this list, removing the first (or all) occurrence of val |
| any | returns a random element of this list |
| swap(index1, index2) | exchange two values in place, by their indexes |
Factory methods
The following methods are also added to the list type, but are meant to be called as list.init, list.init2d, and list.init3d rather than being called on an existing list.
| Method | Returns |
|---|---|
| init(size, initialValue) | list containing size elements with value initialValue |
| init2d(rows, columns, initialValue) | 2D array containing rows rows, each with columns elements with value initialValue |
| init3d(sizeA, sizeB, sizeC, initialValue) | 3D array containing sizeA 2D arrays |
See also: matrixUtil
Example
import "listUtil"
print [1, 2, 3].reversed // prints: [3, 2, 1]
