c - 如何在c中实现(PHP函数)array_map函数？

Question

所有，我想用c语言实现array_map函数。我该怎么做？

void * x_array_map(void * func, Array * arr){
   //TODO
}

谢谢!

Answer 1

这里是一些关于函数作为参数的引用，

How do you pass a function as a parameter in C?

这是我的代码:

#include <stdio.h>
#include <stdlib.h>

#define param_type int

// prototype
param_type* array_map (param_type (*f)(param_type), param_type* arr, int n);

// dummy function
int cube(int x) {
    return x*x*x;
}

int main (){
    int a[3] = {1, 2, 3};
    int* b = array_map(cube, a, 3);
    for (int i = 0; i < 3; ++i) {
        printf("%d\n", b[i]);
    }
    return 0;
}

param_type* array_map (param_type (*f)(param_type), param_type* arr, int n) {
    param_type* result = (param_type*) malloc(n*sizeof(param_type));
    for (int i = 0; i < n; ++i)
        result[i] = f(arr[i]);
    return result;
}