将C移植到Go中，以在if检查中修改变量

I'm trying to port the following C code to Go:

if (x == 0 || x-- == 0) {
    // Stuff
}

This isn't legal in Go because I can't modify x inside the check clause.

What's a good way of representing this in Go without e.g. duplicating the contents of the block?

If x-- is a typo and should be --x, then I would make the changes to x explicit:

if x == 0 || x == 1 {
    x = 0

    // Stuff
} else {
    x--
}

Otherwise, your C code has a bug. If x == 0 is false, then x-- == 0 will also be false because you're using the post-increment operator. Therefore, the code would be equivalent to:

if (x == 0) {
    // Stuff
} else {
    x--;
}

The Go code

    if x != 0 {
        x--
    } else {
        // Stuff
    }

is equivalent to the C code

    if (x == 0 || x-- == 0) {
        // Stuff
    }

For example, in Go,

package main

import (
    "fmt"
)

func main() {
    for _, x := range []int{-42, -2, -1, 0, 1, 2, 42} {
        fmt.Printf("x %d:", x)
        if x != 0 {
            x--
        } else {
            fmt.Printf(" Stuff %d:", x)
        }
        fmt.Printf(" x %d:
", x)
    }
}

Output:

x -42: x -43:
x -2: x -3:
x -1: x -2:
x 0: Stuff 0: x 0:
x 1: x 0:
x 2: x 1:
x 42: x 41:

For example, in C,

#include <stdio.h>

int main() {
    int a[] = {-42,-2,-1,0,1,2,42};
    for (int i = 0; i < (sizeof a)/sizeof a[0]; i++) {
        int x = a[i];
        printf("x %d:", x);
        if (x == 0 || x-- == 0) {
            printf(" Stuff %d:", x);
        }
        printf(" x %d:
", x);
    }
}

Output:

x -42: x -43:
x -2: x -3:
x -1: x -2:
x 0: Stuff 0: x 0:
x 1: x 0:
x 2: x 1:
x 42: x 41: