linux - 在 bash 脚本中一次运行多个循环

Question

下面是我正在运行的脚本

#!/bin/bash

region=('us-east-1' 'eu-central-1')
env=('prod' 'stage')


for region in "${region[@]}"
do
        for env in "${env[@]}"
        do
                echo "$region"
                echo "$env"
        done
done

我得到的输出是

us-east-1
prod
us-east-1
stage
eu-central-1
stage
eu-central-1
stage

但我的期望是得到

us-east-1
prod
us-east-1
stage
eu-central-1
prod
eu-central-1
stage

脚本应该在两种环境条件下运行，但它只在生产环境中运行一次，在舞台环境中运行三次。 我哪里出错了，任何指示或建议将不胜感激

Answer 1

您需要为循环使用与初始数组不同的变量。否则，您将在第一次迭代期间覆盖数组。

这里我为数组和循环变量使用了不同的变量:

#!/bin/bash

regions=('us-east-1' 'eu-central-1')
envs=('prod' 'stage')
    
for region in "${regions[@]}"
do
    for env in "${envs[@]}"
    do
        echo "$region"
        echo "$env"
    done
done

输出:

us-east-1
prod
us-east-1
stage
eu-central-1
prod
eu-central-1
stage

---

PS:另一种选择是使用一串多个单词并让 bash 对其进行迭代:

for a in foo bar
do
    for b in baz qux
    do
        echo "${a}"
        echo "${b}"
    done
done