bash中的複雜文本對齊

鑑於此輸入：

# Lines starting with # stay the same
# Empty lines stay the same
# only lines with comments should change

ls  # show all major directories
              # and other things

cd      # The cd command - change directory  
            # will allow the user to change between file directories

touch             # The touch command, the make file command 
                # allows users to make files using the Linux CLI #  example, cd ~

bar foo baz # foo foo foo

我需要保持以開頭的#行和不包含任何註釋的行保持原樣，但在同一列上對齊所有其他註釋。

期望的輸出：

# Lines starting with # stay the same
# Empty lines stay the same
# Only lines with # in middle should change and be aligned

ls              # show all major directories
                # and other things

cd              # The cd command - change directory  
                # will allow the user to change between file directories

touch           # The touch command, the make file command 
                # allows users to make files using the Linux CLI #  exmaple, cd ~

bar foo baz     # foo foo foo

這是我到目前為止所擁有的：

# Building an array out of input
while IFS=$'\n' read -r; do 
   lines+=("$REPLY") 
done 

# Looping through array and selecting elemnts that need change 
for i in "${lines[@]}"
 do
   if  [[ ${i:0:1} == ';' || $i != *";"* ]];
     then
       echo "DOESNT CHANGE: #### $i"
   else 
       echo "HAS TO CHANGE: #### $i"
       array+=( "${i%%";"*}" );
       array2+=("${i##";"}")
   fi
done

# Trying to find the longest line to decide how much space I need to add for each element
max = ${array[0]}

for n in "${array[@]}" ; do
   ((${#n} > max)) && max=${#n}
   echo  "Length:" ${#n} ${n}
done

#Longest line
echo $max

# Loop for populating array 
for j in "${!array2[@]}" ; do
   echo "${array2[j]} " | sed -e "s/;/$(echo "-%20s ;") /g" 
done

我覺得我做的太多了。我認為應該有一個更簡單的方法來解決這個問題。

如果您的所有命令和參數不包含#, 和一個其他字元（例如字節 1 給出的 ASCII 字元），您可以插入該其他字元作為額外的分隔符並用於column對齊註釋（請參閱此答案）。所以，像：

$ sed $'s/#/\001#/' input-file | column -ets $'\001'
# Lines starting with # stay the same
# Empty lines stay the same
# only lines with comments should change

ls                                        # show all major directories
                                         # and other things

cd                                        # The cd command - change directory
                                         # will allow the user to change between file directories

touch                                     # The touch command, the make file command
                                         # allows users to make files using the Linux CLI #  example, cd ~

bar foo baz                               # foo foo foo

如果您column不支持-e避免消除空行，則可以在空行中添加一些內容（例如，空格或上面使用的分隔符）：

$ sed $'s/#/\001#/;s/^$/\001/' input-file | column -ts $'\001'
# Lines starting with # stay the same
# Empty lines stay the same
# only lines with comments should change

ls                                        # show all major directories
                                         # and other things

cd                                        # The cd command - change directory
                                         # will allow the user to change between file directories

touch                                     # The touch command, the make file command
                                         # allows users to make files using the Linux CLI #  example, cd ~

bar foo baz                               # foo foo foo

引用自：https://unix.stackexchange.com/questions/443618