bash bashrc if: 表达式语法错误
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/14440105/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
bashrc if: Expression Syntax error
提问by Chani
I have written the following .bashrc :
我写了以下 .bashrc ：
# .bashrc
# Source global definitions
if [ -f /etc/bashrc ]; then
. /etc/bashrc
fi
# User specific aliases and functions
function up( )
{
LIMIT=
P=$PWD
for ((i=1; i <= LIMIT; i++))
do
P=$P/..
done
cd $P
export MPWD=$P
}
function back( )
{
LIMIT=
P=$MPWD
for ((i=1; i <= LIMIT; i++))
do
P=${P%/..}
done
cd $P
export MPWD=$P
}
However, after saving, when I did source .bashrc, i got the following error: if: Expression Syntax.
但是，保存后，当我这样做时source .bashrc，出现以下错误： if: Expression Syntax.
What am I doing wrong ? I googled a while but no avail.
我究竟做错了什么 ？我用谷歌搜索了一段时间，但无济于事。
回答by kojiro
if: Expression Syntax
is not an error bash would give you. Perhaps your shell is not bash. In fact, as long as ifstands alone, any error would not be with ifitself:
不是 bash 会给你的错误。也许你的 shell 不是 bash。事实上，只要if单独存在，任何错误都不会发生在if自己身上：
$ if [somethingswrong]; then fail; fi # error, then `[` command must have space around it.
-bash: [somethingswrong]: command not found
You can check your shell by echoing $SHELL, and you can check which version of bash with $BASH_VERSION. (If the latter is unset, your shell is not bash.)
你可以通过 echo 来检查你的 shell $SHELL，你可以用$BASH_VERSION. （如果后者未设置，则您的 shell 不是 bash。）
