Linux [[ 带有 bash 的条件表达式中的语法错误
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时间:2020-08-06 04:53:15 来源:igfitidea点击:
Syntax error in [[ conditional expression with bash
提问by Sandra Schlichting
When I execute this
当我执行这个
regex='^[-a-z0-9]+$'
string='abcd1--'
if [[ $string =~ $regex ] -a ![ grep - "--" ]]
then
echo "valid"
else
echo "not valid"
fi
I get
我得到
~$ sh t.sh
t.sh: line 3: syntax error in conditional expression
t.sh: line 3: syntax error near `]'
t.sh: line 3: `if [[ $string =~ $regex ] -a [ grep - "--" ]]'
~$
It is suppose to return not valid
.
它是假设返回not valid
。
Can someone figure out what's wrong?
有人能弄清楚出了什么问题吗?
采纳答案by Mat
You're mixing [
and [[
syntax in a strange way.
你以一种奇怪的方式混合[
和[[
语法。
Try:
尝试:
if [[ ( $string =~ $regex ) && !( $string =~ "--" ) ]]
and check bash's man page.
并检查 bash 的手册页。