The connector for Shell script is a comma, not a period in English

As an example:

gawk 'begin{var["a"]=1var["g"]=2var["m"]=3var["u"]=4Asort (var,test) for(Iinchtest) Print"Index:"I"-Value:", test[1]}'

When you hit enter, you can output

4  1  1  12  13  1 

The script in front of the time because the electronic version of the book is completely unclear, I look at the original write PHP connector (full period), the result is always wrong

For example, I changed the comma of the above program to a point, the error is as follows

gawk: cmd. Line:7"Index:". ". " -value:". test[1]gawk: cmd. Line:7:               ^ syntax error

The connector for Shell script is a comma, not a period in English