cpp_prac/vector/vec.cc

#include "vec.h"
#include <cstddef>
#include <cstring>
#include <iostream>

Vec::Vec() : Vec(INITIAL_LEN) {}

Vec::Vec(std::size_t size) : cap(size), w_idx(0), arr(new T[size]) {
    std::cout << "Allocating vector of size " << size << std::endl;
}

Vec::Vec(std::initializer_list<T> il) : Vec(il.size()) {
    for (auto &elem : il) push_back(std::move(elem));
}

Vec::~Vec() {
    std::cout << "De-allocating vector" << std::endl;

    if (arr)
        delete[] arr;
}

T &Vec::operator[](std::size_t idx) const noexcept {
    if (idx < w_idx)
        return arr[idx];

    exit(1);
}

void Vec::push_back(const T &value) {
    arr[w_idx++] = value;

    if (w_idx == cap)
        resize(cap * 2);
}

void Vec::push_back(T &&value) {
    arr[w_idx++] = std::move(value);

    if (w_idx == cap)
        resize(cap * 2);
}

std::size_t Vec::size() const { return w_idx; }

std::size_t Vec::capacity() const noexcept { return cap; }

void Vec::resize(std::size_t newsize) {
    std::cout << "Reallocating: " << cap << " to " << newsize << std::endl;

    T *newarr = new T[newsize];
    std::move(arr, arr + w_idx, newarr);
    delete[] arr;
    arr = newarr;
    cap = newsize;
}

void Vec::pop_back() noexcept { --w_idx; }

void Vec::clear() noexcept {
#ifdef REALCLEAR
    delete[] arr;
    arr = new T[INITIAL_LEN];
    cap = INITIAL_LEN;
#endif

    w_idx = 0;
}