bash 问题中的字符串标记化

Question

    tokens='a,b'
    IFS=',' read -ra a <<<$tokens
    for i in "${a[@]}"; do
       echo "$i |"
    done

输出

    a b |

但

    IFS=',' read -ra a <<<'a,b'
    for i in "${a[@]}"; do
       echo "$i |"
    done

输出正确

a |
b |

如何使第一个工作？我很困惑。

Answer 1

$token 周围需要双引号

 cat a

 tokens='a,b'
     IFS=',' read -ra a <<< "$tokens"
     for i in "${a[@]}"; do
        echo "$i |"
     done

 ./a
 a |
 b |