shell 获取变量是什么数据类型

?

1 2 3 4 5 6 7 8 9 10 11 12

function check(){     local a="$1"     printf "%d" "$a" &>/dev/null && echo "integer" && return     printf "%d" "$(echo $a|sed 's/^[+-]\?0\+//')" &>/dev/null && echo "integer" && return     printf "%f" "$a" &>/dev/null && echo "number" && return     [ ${#a} -eq 1 ] && echo "char" && return     echo "string" }   echo $(check "xx")   输出: string