mirror of https://github.com/japl-lang/japl.git
193 lines
6.5 KiB
Nim
193 lines
6.5 KiB
Nim
# Copyright 2020 Mattia Giambirtone
|
|
#
|
|
# Licensed under the Apache License, Version 2.0 (the "License");
|
|
# you may not use this file except in compliance with the License.
|
|
# You may obtain a copy of the License at
|
|
#
|
|
# http://www.apache.org/licenses/LICENSE-2.0
|
|
#
|
|
# Unless required by applicable law or agreed to in writing, software
|
|
# distributed under the License is distributed on an "AS IS" BASIS,
|
|
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
# See the License for the specific language governing permissions and
|
|
# limitations under the License.
|
|
|
|
# Implementation of a custom list data type for JAPL objects (used also internally by the VM)
|
|
|
|
{.experimental: "implicitDeref".}
|
|
import iterable
|
|
import ../memory
|
|
import baseObject
|
|
import strformat
|
|
|
|
|
|
type ArrayList*[T] = object of Iterable
|
|
## Implementation of a simple dynamic
|
|
## array with amortized O(1) append complexity
|
|
## and O(1) complexity when popping/deleting
|
|
## the last element
|
|
container*: ptr UncheckedArray[T]
|
|
|
|
|
|
proc newArrayList*[T](): ptr ArrayList[T] =
|
|
## Allocates a new, empty array list
|
|
result = allocateObj(ArrayList[T], ObjectType.List)
|
|
result.capacity = 0
|
|
result.container = nil
|
|
result.length = 0
|
|
|
|
|
|
proc append*[T](self: ptr ArrayList[T], elem: T) =
|
|
## Appends an object to the end of the list
|
|
## in amortized constant time (~O(1))
|
|
if self.capacity <= self.length:
|
|
self.capacity = growCapacity(self.capacity)
|
|
self.container = resizeArray(T, self.container, self.length, self.capacity)
|
|
self.container[self.length] = elem
|
|
self.length += 1
|
|
|
|
|
|
proc pop*[T](self: ptr ArrayList[T], idx: int = -1): T =
|
|
## Pops an item from the list. By default, the last
|
|
## element is popped, in which case the operation's
|
|
## time complexity is O(1). When an arbitrary element
|
|
## is popped, the complexity rises to O(k) where k
|
|
## is the number of elements that had to be shifted
|
|
## by 1 to avoid empty slots
|
|
var idx = idx
|
|
if self.length == 0:
|
|
raise newException(IndexDefect, "pop from empty ArrayList")
|
|
if idx == -1:
|
|
idx = self.length - 1
|
|
if idx notin 0..self.length - 1:
|
|
raise newException(IndexDefect, &"ArrayList index out of bounds: {idx} notin 0..{self.length - 1}")
|
|
result = self.container[idx]
|
|
if idx != self.length - 1:
|
|
for i in countup(idx, self.length - 1):
|
|
self.container[i] = self.container[i + 1]
|
|
self.capacity -= 1
|
|
self.length -= 1
|
|
|
|
|
|
proc `[]`*[T](self: ptr ArrayList[T], idx: int): T =
|
|
## Retrieves an item from the list, in constant
|
|
## time
|
|
if self.length == 0:
|
|
raise newException(IndexDefect, &"ArrayList index out of bounds: : {idx} notin 0..{self.length - 1}")
|
|
if idx notin 0..self.length - 1:
|
|
raise newException(IndexDefect, &"ArrayList index out of bounds: {idx} notin 0..{self.length - 1}")
|
|
result = self.container[idx]
|
|
|
|
|
|
proc `[]`*[T](self: ptr ArrayList[T], slice: Hslice[int, int]): ptr ArrayList[T] =
|
|
## Retrieves a subset of the list, in O(k) time where k is the size
|
|
## of the slice
|
|
if self.length == 0:
|
|
raise newException(IndexDefect, "ArrayList index out of bounds")
|
|
if slice.a notin 0..self.length - 1 or slice.b notin 0..self.length:
|
|
raise newException(IndexDefect, "ArrayList index out of bounds")
|
|
result = newArrayList[T]()
|
|
for i in countup(slice.a, slice.b - 1):
|
|
result.append(self.container[i])
|
|
|
|
|
|
proc `[]=`*[T](self: ptr ArrayList[T], idx: int, obj: T) =
|
|
## Assigns an object to the given index, in constant
|
|
## time
|
|
if self.length == 0:
|
|
raise newException(IndexDefect, "ArrayList is empty")
|
|
if idx notin 0..self.length - 1:
|
|
raise newException(IndexDefect, "ArrayList index out of bounds")
|
|
self.container[idx] = obj
|
|
|
|
|
|
proc delete*[T](self: ptr ArrayList[T], idx: int) =
|
|
## Deletes an object from the given index.
|
|
## This method shares the time complexity
|
|
## of self.pop()
|
|
if self.length == 0:
|
|
raise newException(IndexDefect, "delete from empty ArrayList")
|
|
if idx notin 0..self.length - 1:
|
|
raise newException(IndexDefect, &"ArrayList index out of bounds: {idx} notin 0..{self.length - 1}")
|
|
discard self.pop(idx)
|
|
|
|
|
|
proc contains*[T](self: ptr ArrayList[T], elem: T): bool =
|
|
## Returns true if the given object is present
|
|
## in the list, false otherwise. O(n) complexity
|
|
if self.length > 0:
|
|
for i in 0..self.length - 1:
|
|
if self[i] == elem:
|
|
return true
|
|
return false
|
|
|
|
|
|
proc high*[T](self: ptr ArrayList[T]): int =
|
|
## Returns the index of the last
|
|
## element in the list, in constant time
|
|
if self.length == 0:
|
|
raise newException(IndexDefect, "ArrayList is empty")
|
|
result = self.length - 1
|
|
|
|
|
|
proc len*[T](self: ptr ArrayList[T]): int =
|
|
## Returns the length of the list
|
|
## in constant time
|
|
result = self.length
|
|
|
|
|
|
iterator pairs*[T](self: ptr ArrayList[T]): tuple[key: int, val: T] =
|
|
## Implements pairwise iteration (similar to python's enumerate)
|
|
for i in countup(0, self.length - 1):
|
|
yield (key: i, val: self[i])
|
|
|
|
|
|
iterator items*[T](self: ptr ArrayList[T]): T =
|
|
## Implements iteration
|
|
for i in countup(0, self.length - 1):
|
|
yield self[i]
|
|
|
|
|
|
proc reversed*[T](self: ptr ArrayList[T], first: int = -1, last: int = 0): ptr ArrayList[T] =
|
|
## Returns a reversed version of the given list, from first to last.
|
|
## First defaults to -1 (the end of the list) and last defaults to 0 (the
|
|
## beginning of the list)
|
|
var first = first
|
|
if first == -1:
|
|
first = self.length - 1
|
|
result = newArrayList[T]()
|
|
for i in countdown(first, last):
|
|
result.append(self[i])
|
|
|
|
|
|
proc extend*[T](self: ptr ArrayList[T], other: seq[T]) =
|
|
## Iteratively calls self.append() with the elements
|
|
## from a nim sequence
|
|
for elem in other:
|
|
self.append(elem)
|
|
|
|
|
|
proc extend*[T](self: ptr ArrayList[T], other: ptr ArrayList[T]) =
|
|
## Iteratively calls self.append() with the elements
|
|
## from another ArrayList
|
|
for elem in other:
|
|
self.append(elem)
|
|
|
|
|
|
proc `$`*[T](self: ptr ArrayList[T]): string =
|
|
## Returns a string representation
|
|
## of self
|
|
result = "["
|
|
if self.length > 0:
|
|
for i in 0..self.length - 1:
|
|
result = result & $self.container[i]
|
|
if i < self.length - 1:
|
|
result = result & ", "
|
|
result = result & "]"
|
|
|
|
|
|
proc getIter*[T](self: ptr ArrayList[T]): Iterator =
|
|
## Returns the iterator object of the
|
|
## arraylist
|
|
result = allocate(Iterator, )
|