Convert multiline bash script to an one line

Question

I have script like this:

for f in *
do
    #if condition
    if [[ -d $f ]]; then
        echo "$f is a directory";
    else
        echo "$f is not a directory";
    fi
done

Is it possible to convert multiple script into 1 line like this? (maybe I need to delete # comment statement(s)).

for f in *; do  if [[ -d $f ]]; then  echo "$f is a directory"; else  echo "$f is not a directory"; fi done

I can change for statement syntax in above script like:

1. for f in *
2. for f in *;
3. for f in *;do

Same applies to if condition. In all the cases it should generate a proper 1 line. What could be the automated way to do this?

Solution

Parsing bash in oneliners is a hard task...

Anyway as a starting point, here goes a suggestion to cover very specific situations like the one presented

perl -p0e '
    s/#.*//; 
    s/;?\s+(do|done|then|else|fi)\s+/ ; $1 /g '

Comments

[muru]

what's the advantage? On the contrary, writing compound commands like this in one line actually harms readability.

[snoop]

You are right, but case where automation is required needs 1 liner, instead of writing a large script.

[snoop]

If you know about plink which is a commandline putty version works perfectly with command provided at commandline. I mean executing script compared with command is quite tedious and erroneous using plink.

[muru]

If it has problems with multi-line commands, then, no, plink doesn't work "perfectly". I have never had any problems with multiline commands using the ssh tool on Linux systems.

[snoop]

I will give you another example, If you ever worked on networking devices such as Cisco Firewall, Cisco Router, Mipu Router etc. These type of N/W devices only understand commands, no script. Also, if we fire script on target machine its internally get copied somewhere on target system and for that it should have space.

[muru]

you seem to have some serious confusion. There is a difference between a script and multi-line command. The former is a file, the latter is just a multi-line command. If the target system understands bash, it will understand multiline commands just fine. Do your Cisco devices understand bash? If no, what is the relevance of those to this question?

[snoop]

Yes Cisco device understand it.

[muru]

Then they understand multiline commands.

[terdon]

You realize that both the one-line version and the multiline version can be pasted directly into the terminal, right? Neither one of those is a script, they are both commands than can be run directly in the terminal.

[snoop]

Yeah, writing generic program for this problem is difficult, but this is fine example for this situation.

[nickchalkida]

Executes the awk command in quotes with input from script.txt. More from the awk manual ... I am busy ...