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falcon/collections/array

Generic ordered-list type for Falcon.

Array<T> is a generic struct backed by an FFI C++ implementation.

Installation

import "libs/collections/array/array.fal";

In your falcon.yml:

dependencies:
  - array

Type

struct Array <T> { ... }

T may be any primitive (int, float, bool, string) or struct type.

Routines

New() -> (Array<T> arr)

Creates a new, empty array. 

Array<int> nums = Array.New();

Size() -> (int size)

Returns the number of elements. 

int n = nums.Size();

IsEmpty() -> (bool empty)

bool e = nums.IsEmpty();

GetIndex(int index) -> (T value)

Returns the element at position index (0-based). Also invoked by the arr[i] index syntax. 

int v = nums.GetIndex(0);
int v = nums[0];           // equivalent

SetIndex(int index, T value) -> ()

Replaces the element at position index. 

nums.SetIndex(0, 42);

PushBack(T value) -> ()

Appends to the end. 

nums.PushBack(99);

PopBack() -> (T value)

Removes and returns the last element. 

int last = nums.PopBack();

Insert(int index, T value) -> ()

Inserts before position index. index == Size() appends. 

nums.Insert(0, 10);   // prepend

Erase(int index) -> ()

Removes the element at index. 

nums.Erase(1);

Clear() -> ()

Removes all elements. 

nums.Clear();

Contains(T value) -> (bool found)

bool has = nums.Contains(42);

IndexOf(T value) -> (int index)

Returns the index of the first occurrence, or -1. 

int pos = nums.IndexOf(42);

Index syntax

arr[i] desugars to arr.GetIndex(i) in the interpreter.

Syntax note

Array<T> uses the standard generic struct syntax — no uses or requires clause is needed. The type parameter is simply declared in angle brackets:

struct Array <T> { ... }          // definition
Array<int>    nums = Array.New(); // monomorphised use
Array<string> strs = Array.New();

Running the tests

falcon-test libs/collections/array/tests/run_tests.fal

Full example

import "libs/collections/array/array.fal";

autotuner ArrayDemo (int a, int b, int c) -> (int sum) {
    sum = 0;
    start -> run;
    state run {
        Array<int> nums = Array.New();
        nums.PushBack(a);
        nums.PushBack(b);
        nums.PushBack(c);
        sum = nums[0] + nums[1] + nums[2];
        terminal;
    }
}