ReadonlyArray
Value members
Concrete methods
Combines two or more arrays.
Combines two or more arrays.
- Value Params
- items
Additional items to add to the end of array1.
Returns an iterable of key, value pairs for every entry in the array
Returns an iterable of key, value pairs for every entry in the array
Determines whether all the members of an array satisfy the specified test.
Determines whether all the members of an array satisfy the specified test.
- Value Params
- predicate
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.
- thisArg
An 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.
Determines whether all the members of an array satisfy the specified test.
- Value Params
- predicate
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.
- thisArg
An 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.
Returns the elements of an array that meet the condition specified in a callback function.
- Value Params
- predicate
A function that accepts up to three arguments. The filter method calls the predicate function one time for each element in the array.
- thisArg
An 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.
Returns the elements of an array that meet the condition specified in a callback function.
- Value Params
- predicate
A function that accepts up to three arguments. The filter method calls the predicate function one time for each element in the array.
- thisArg
An 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 value of the first element in the array where predicate is true, and undefined otherwise.
Returns the value of the first element in the array where predicate is true, and undefined otherwise.
- Value Params
- predicate
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.
- thisArg
If 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.
Returns the index of the first element in the array where predicate is true, and -1 otherwise.
- Value Params
- predicate
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.
- thisArg
If 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 new array with all sub-array elements concatenated into it recursively up to the specified depth.
Returns a new array with all sub-array elements concatenated into it recursively up to the specified depth.
- Value Params
- depth
The maximum recursion depth
Calls a defined callback function on each element of an array. Then, flattens the result into a new array. This is identical to a map followed by flat with depth 1.
Calls a defined callback function on each element of an array. Then, flattens the result into a new array. This is identical to a map followed by flat with depth 1.
- Value Params
- callback
A function that accepts up to three arguments. The flatMap method calls the callback function one time for each element in the array.
- thisArg
An object to which the this keyword can refer in the callback function. If thisArg is omitted, undefined is used as the this value.
Performs the specified action for each element in an array.
Performs the specified action for each element in an array.
- Value Params
- callbackfn
A function that accepts up to three arguments. forEach calls the callbackfn function one time for each element in the array.
- thisArg
An object to which the this keyword can refer in the callbackfn function. If thisArg is omitted, undefined is used as the this value.
Determines whether an array includes a certain element, returning true or false as appropriate.
Determines whether an array includes a certain element, returning true or false as appropriate.
- Value Params
- fromIndex
The position in this array at which to begin searching for searchElement.
- searchElement
The element to search for.
Returns the index of the first occurrence of a value in an array.
Returns the index of the first occurrence of a value in an array.
- Value Params
- fromIndex
The array index at which to begin the search. If fromIndex is omitted, the search starts at index 0.
- searchElement
The value to locate in the array.
Adds all the elements of an array separated by the specified separator string.
Adds all the elements of an array separated by the specified separator string.
- Value Params
- separator
A string used to separate one element of an array from the next in the resulting String. If omitted, the array elements are separated with a comma.
Returns the index of the last occurrence of a specified value in an array.
Returns the index of the last occurrence of a specified value in an array.
- Value Params
- fromIndex
The array index at which to begin the search. If fromIndex is omitted, the search starts at the last index in the array.
- searchElement
The value to locate in the array.
Calls a defined callback function on each element of an array, and returns an array that contains the results.
Calls a defined callback function on each element of an array, and returns an array that contains the results.
- Value Params
- callbackfn
A function that accepts up to three arguments. The map method calls the callbackfn function one time for each element in the array.
- thisArg
An object to which the this keyword can refer in the callbackfn 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.
- Value Params
- callbackfn
A function that accepts up to four arguments. The reduce method calls the callbackfn function one time for each element in the array.
- initialValue
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.
- Value Params
- callbackfn
A function that accepts up to four arguments. The reduceRight method calls the callbackfn function one time for each element in the array.
- initialValue
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.
- Value Params
- callbackfn
A function that accepts up to four arguments. The reduceRight method calls the callbackfn function one time for each element in the array.
- initialValue
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. 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.
- Value Params
- callbackfn
A function that accepts up to four arguments. The reduce method calls the callbackfn function one time for each element in the array.
- initialValue
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.
Returns a section of an array.
Returns a section of an array.
- Value Params
- end
The end of the specified portion of the array. This is exclusive of the element at the index 'end'.
- start
The beginning of the specified portion of the array.
Determines whether the specified callback function returns true for any element of an array.
Determines whether the specified callback function returns true for any element of an array.
- Value Params
- predicate
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.
- thisArg
An object to which the this keyword can refer in the predicate function. If thisArg is omitted, undefined is used as the this value.