Readonly
[unscopables]Is an object whose properties have the value 'true' when they will be absent when used in a 'with' statement.
Optional
Readonly
[unscopables]?: booleanIs an object whose properties have the value 'true' when they will be absent when used in a 'with' statement.
Optional
length?: booleanGets or sets the length of the array. This is a number one higher than the highest index in the array.
Static
Readonly
[species]Gets or sets the length of the array. This is a number one higher than the highest index in the array.
Returns the value of the first element in the array where predicate is true, and undefined otherwise.
find calls predicate once for each element of the array, in ascending order, until it finds one where predicate returns true. If such an element is found, find immediately returns that element value. Otherwise, find returns undefined.
Optional
thisArg: anyIf provided, it will be used as the this value for each invocation of predicate. If it is not provided, undefined is used instead.
Returns the index of the first element in the array where predicate is true, and -1 otherwise.
find calls predicate once for each element of the array, in ascending order, until it finds one where predicate returns true. If such an element is found, findIndex immediately returns that element index. Otherwise, findIndex returns -1.
Optional
thisArg: anyIf provided, it will be used as the this value for each invocation of predicate. If it is not provided, undefined is used instead.
Changes all array elements from start
to end
index to a static value
and returns the modified array
value to fill array section with
Optional
start: numberindex to start filling the array at. If start is negative, it is treated as length+start where length is the length of the array.
Optional
end: numberindex to stop filling the array at. If end is negative, it is treated as length+end.
Returns the this object after copying a section of the array identified by start and end to the same array starting at position target
If target is negative, it is treated as length+target where length is the length of the array.
If start is negative, it is treated as length+start. If end is negative, it is treated as length+end.
Optional
end: numberIf not specified, length of the this object is used as its default value.
Determines whether an array includes a certain element, returning true or false as appropriate.
The element to search for.
Optional
fromIndex: numberThe position in this array at which to begin searching for searchElement.
Returns the value of the last element in the array where predicate is true, and undefined otherwise.
findLast calls predicate once for each element of the array, in descending order, until it finds one where predicate returns true. If such an element is found, findLast immediately returns that element value. Otherwise, findLast returns undefined.
Optional
thisArg: anyIf provided, it will be used as the this value for each invocation of predicate. If it is not provided, undefined is used instead.
Returns the index of the last element in the array where predicate is true, and -1 otherwise.
findLastIndex calls predicate once for each element of the array, in descending order, until it finds one where predicate returns true. If such an element is found, findLastIndex immediately returns that element index. Otherwise, findLastIndex returns -1.
Optional
thisArg: anyIf provided, it will be used as the this value for each invocation of predicate. If it is not provided, undefined is used instead.
Returns a copy of an array with its elements sorted.
Optional
compareFn: ((a: T, b: T) => number)Function used to determine the order of the elements. It is expected to return a negative value if the first argument is less than the second argument, zero if they're equal, and a positive value otherwise. If omitted, the elements are sorted in ascending, ASCII character order.
[11, 2, 22, 1].toSorted((a, b) => a - b) // [1, 2, 11, 22]
Copies an array and removes elements and, if necessary, inserts new elements in their place. Returns the copied array.
The zero-based location in the array from which to start removing elements.
The number of elements to remove.
Rest
...items: T[]Elements to insert into the copied array in place of the deleted elements.
The copied array.
Copies an array and removes elements while returning the remaining elements.
The zero-based location in the array from which to start removing elements.
Optional
deleteCount: numberThe number of elements to remove.
A copy of the original array with the remaining elements.
Copies an array, then overwrites the value at the provided index with the given value. If the index is negative, then it replaces from the end of the array.
The index of the value to overwrite. If the index is negative, then it replaces from the end of the array.
The value to write into the copied array.
The copied array with the updated value.
Returns a string representation of an array. The elements are converted to string using their toLocaleString methods.
Optional
options: NumberFormatOptions & DateTimeFormatOptionsAppends new elements to the end of an array, and returns the new length of the array.
Rest
...items: T[]New elements to add to the array.
Combines two or more arrays. This method returns a new array without modifying any existing arrays.
Rest
...items: ConcatArray<T>[]Additional arrays and/or items to add to the end of the array.
Combines two or more arrays. This method returns a new array without modifying any existing arrays.
Adds all the elements of an array into a string, separated by the specified separator string.
Optional
separator: stringA string used to separate one element of the array from the next in the resulting string. If omitted, the array elements are separated with a comma.
Returns a copy of a section of an array. For both start and end, a negative index can be used to indicate an offset from the end of the array. For example, -2 refers to the second to last element of the array.
Optional
start: numberThe beginning index of the specified portion of the array. If start is undefined, then the slice begins at index 0.
Optional
end: numberThe end index of the specified portion of the array. This is exclusive of the element at the index 'end'. If end is undefined, then the slice extends to the end of the array.
Sorts an array in place. This method mutates the array and returns a reference to the same array.
Optional
compareFn: ((a: T, b: T) => number)Function used to determine the order of the elements. It is expected to return a negative value if the first argument is less than the second argument, zero if they're equal, and a positive value otherwise. If omitted, the elements are sorted in ascending, ASCII character order.
[11,2,22,1].sort((a, b) => a - b)
Removes elements from an array and, if necessary, inserts new elements in their place, returning the deleted elements.
The zero-based location in the array from which to start removing elements.
Optional
deleteCount: numberThe number of elements to remove.
An array containing the elements that were deleted.
Removes elements from an array and, if necessary, inserts new elements in their place, returning the deleted elements.
The zero-based location in the array from which to start removing elements.
The number of elements to remove.
Rest
...items: T[]Elements to insert into the array in place of the deleted elements.
An array containing the elements that were deleted.
Inserts new elements at the start of an array, and returns the new length of the array.
Rest
...items: T[]Elements to insert at the start of the array.
Returns the index of the first occurrence of a value in an array, or -1 if it is not present.
The value to locate in the array.
Optional
fromIndex: numberThe array index at which to begin the search. If fromIndex is omitted, the search starts at index 0.
Returns the index of the last occurrence of a specified value in an array, or -1 if it is not present.
The value to locate in the array.
Optional
fromIndex: numberThe array index at which to begin searching backward. If fromIndex is omitted, the search starts at the last index in the array.
Determines whether all the members of an array satisfy the specified test.
A function that accepts up to three arguments. The every method calls the predicate function for each element in the array until the predicate returns a value which is coercible to the Boolean value false, or until the end of the array.
Optional
thisArg: anyAn object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Determines whether all the members of an array satisfy the specified test.
A function that accepts up to three arguments. The every method calls the predicate function for each element in the array until the predicate returns a value which is coercible to the Boolean value false, or until the end of the array.
Optional
thisArg: anyAn object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Determines whether the specified callback function returns true for any element of an array.
A function that accepts up to three arguments. The some method calls the predicate function for each element in the array until the predicate returns a value which is coercible to the Boolean value true, or until the end of the array.
Optional
thisArg: anyAn object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Performs the specified action for each element in an array.
A function that accepts up to three arguments. forEach calls the callbackfn function one time for each element in the array.
Optional
thisArg: anyAn object to which the this keyword can refer in the callbackfn function. If thisArg is omitted, undefined is used as the this value.
Returns the elements of an array that meet the condition specified in a callback function.
A function that accepts up to three arguments. The filter method calls the predicate function one time for each element in the array.
Optional
thisArg: anyAn object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Returns the elements of an array that meet the condition specified in a callback function.
A function that accepts up to three arguments. The filter method calls the predicate function one time for each element in the array.
Optional
thisArg: anyAn object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.
Calls the specified callback function for all the elements in an array. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
Calls the specified callback function for all the elements in an array. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
A function that accepts up to four arguments. The reduce method calls the callbackfn function one time for each element in the array.
If initialValue is specified, it is used as the initial value to start the accumulation. The first call to the callbackfn function provides this value as an argument instead of an array value.
Calls the specified callback function for all the elements in an array, in descending order. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
Calls the specified callback function for all the elements in an array, in descending order. The return value of the callback function is the accumulated result, and is provided as an argument in the next call to the callback function.
A function that accepts up to four arguments. The reduceRight method calls the callbackfn function one time for each element in the array.
If initialValue is specified, it is used as the initial value to start the accumulation. The first call to the callbackfn function provides this value as an argument instead of an array value.
Static
isStatic
fromCreates an array from an async iterator or iterable object.
Creates an array from an async iterator or iterable object.
inserts an item at the specified index, shifting all items ahead of it one position to the front.
negative indices are also supported for indicating the position of the newly added item after the array's length has incremented.
swap the position of two items by their index.
if any of the two indices is out of bound, then appropriate number of empty elements will be created to fill the gap;
similar to how index-based assignment works (i.e. my_list[off_bound_index] = "something"
will increase my_list
's length).
the map
array method needs to have its signature corrected, because apparently, javascript internally creates a new instance of this
, instead of a new instance of an Array
.
the signature of the map method in typescript is misleading, because:
map<U>(callbackfn: (value: T, index: number, array: T[]) => U, thisArg?: any): U[]
map<U>(callbackfn: (value: T, index: number, array: typeof this<T>) => U, thisArg?: any): typeof this<U>
meaning that in our case, array
is of type List<T>
(or a subclass thereof), and the return value is also List<U>
(or a subclass) instead of Array<U>
.
in addition, it also means that a new instance of this collection (List
) is created, in order to fill it with the return output.
this is perhaps the desired behavior for many uses, but for my specific use of "reference counting" and "list-like collection of signals",
this feature does not bode well, as I need to be able to account for each and every single instance.
surprise instances of this class are not welcomed, since it would introduce dead dependencies in my "directed acyclic graphs" for signals.
sets the value at the specified index.
prefer using this method instead of index-based assignment, because subclasses may additionally cary out more operations with this method.
and for attaining compatibility between List
and its subclasses, it would be in your best interest to use the set
method.
my_list[index] = "hello"
my_list.set(index, "hello")
Static
fromStatic
of
a very simple python-like
List
s class, that allows for in-between insertions, deletions, and replacements, to keep the list compact.